Mat %1, 1888.] 



FOREST AND STREAM. 



847 



Address all communications to the Forest and Stream Publish- 

 ing Co. 



EARTHWORMS. 



THIS is the somewhat technical name for the same ani- 

 mals with which every one becomes acquainted in 

 boyhood under the names of "fishworms" and "angle- 

 worms." I suppose they are called earthworms from the 

 peculiar way in which they burrow their holes, namely, by 

 swallowing the earth and passing it through their bodies. 

 There is a popular notion, too, that these animals feed upon 

 earth; this of course in its literal sense is quite erroneous; 

 still it is true that they swallow earth, in which is decaying 

 organic matter, for the food it contains, discharging it again 

 from their bodies when the nutritious matter has been ex- 

 tracted. Everybody has noticed the coiled castings lying 

 near their holes after a rain. I have never seen any expla- 

 nation of the fact, but I suppose they come to the surface in 

 time of a heavy rain, when their holes have become filled 

 with water, to escape being drowned. The soil having be- 

 come very wet, their burrows cave in, and the worms have 

 to find their way to the surface by digging a new hole. 

 Having arrived at the top they discharge from their bodies 

 the earth they have swallowed on their way. It is often to 

 be noticed, too, when the ground has been thoroughly wet, 

 that large numbers of them lie on the surface in a stupid, 

 inactive condition, or sometimes quite dead. I think the 

 explanation of this is that the ground is so saturated with 

 water that they are unable to live in it, and being exposed 

 to the air and rain at the surface they are rendered paitially 

 insensible or, under sufficiently severe exposure, quite dead. 



Probably earthworms come to the surface regularly at 

 night time. 1 have often seen a brood of ducks go out in 

 the early evening to feed upon them. I am inclined to think 

 that toads make a diet of them too at this time. At any 

 rate their near relations, the frogs, eat them with apparent 

 relish. Another animal said to make them a considerable 

 part of its diet is the mole; this creature uses his sharp- 

 pointed nose to some purpose here, for he burrows into their 

 holes and devours the worms in iheir own retreat. He is 

 credited with thus serving a useful purpose in stirring up 



the soil. 



The earthworms themselves live chiefly, if not entirely, 

 upon vegetable food. Their object in coming to the surface 

 at night is to obtain food. They are said to cautiously ex- 

 tend a part of their body out of the holes, move it about in 

 search of a leaf or twig and, having found one, draw it after 

 them into their burrows. In this way they lay up a store of 

 food, eating it when it has undergone partial decomposition. 



In structure, the earthworm, as any one can see from an 

 examination, is made up of a large number of rings placed 

 behind one another. Of these rings, in a large specimen 

 there are not less than one hundred and fifty. The con- 

 strictions where the rings unite are continued inward to 

 form septa, so that the body of the worm is made up of a 

 series of chambers corresponding in number to the rings. 

 The chambers, of course, communicate with one another in- 

 ternally. The most anterior ring is an incomplete one, be- 

 ing only a half ring and forming the upper lip. All the 

 others are complete. The mouth, situated under the upper 

 lip in the second ring, opens into a pretty capacious cham- 

 ber, called the buccal pouch. This pouch is reversible; by 

 turning it inside out, the animal can not only empty it of 

 objectionable matter it may have swallowed, but perhaps 

 use it also as a sucking organ. By passing the fingers for- 

 ward along the anterior part of the body, a worm may be 

 made to evert its pouch. This organ opens posteriorly into 

 a tube which runs straight through the body, terminating in 

 the last ring. This tube, of course, is the digestive or ali- 

 mentary canal . It expands, in the anterior region of the 

 body, into an organ corresponding to the stomach of the 

 higher animals, and it also has opening into it the duct of a 

 large organ which performs the office of a liver. The ali- 

 mentary canal can readily be seen through the skin of a 

 worm, appearing as a dark line. 



The back or dorsal surface of an earthworm can always 

 be readily distinguished from its ventral surface by the dif- 

 ference in color between the two; the dorsal surface being 

 brownish red, the ventral of a paler hue. Every one must 

 have noticed, too, that the body of an earthworm shows iri- 

 descence or play of colors. This is due to the peculiar 

 microscopical structure of a thin cuticle which covers over 

 the entire body of the animal like a sheath. If a worm be 

 placed in alcohol and left a few hours, this cuticle can be 

 peeled off. A piece of it placed under the microscope will 

 then show the cause of the play of colors. It will be seen 

 to be marked by rows of fine lines, which in fact are minute 

 parallel ridges. The rays of light falling upon these ridges 

 and being reflected from them are broken up into their com- 

 ponent colors and thus the iridescence produced. A proof 

 of this is that when the worm is stretched the play of colors 

 is interfered with, the explanation being that the stretching 

 causes the ridges to be flattened out. The cuticle, which 

 forms the sheath, consists of a material closely resembling 

 horn in its physical properties. Its office is undoubtedly the 

 protection of the soft muscular parts. 



In a good sized specimen one can usually readily see in 

 the dorsal surface, lying above the digestive tube, a narrow 

 red thread. By careful watching this thread may be seen 

 to rhythmically enlarge and contract. It is, in fact, a blood- 

 vessel and it is by its alternate expansions and contractions 

 that the blood is circulated through the body. The worm 

 has no heart or at least no more than what is represented by 

 this blood-vessel. Besides this dorsal vessel there are others 

 connected with it and supplying all parts of the body. Not 

 to go too much into detail I will only say that besides the 

 blood in these vessels there is another white fluid in the gen- 

 eral cavity of the body sometimes spoken of as blood. Curi- 

 ously enough this latter fluid is always the home of one or 

 more species of microscopic animal parasites. There are few 

 animals, indeed, that are not the unwilling hosts of some 

 degraded creatures that maintain life only by preying on 

 that of another. 



If an earthworm be gently drawn through the fingers from 

 the head to the tail the ventral surface will be found to offer 

 a slighii resistance. This is due to the presence of short stiff 

 bristles, called setse, which serve as organs of locomotion. 

 In a large specimen they can readily be seen. They are ar- 

 ranged in four double rows running parallel along nearly the 

 whole length of the body. The outer double rows are just be- 

 low the lune where the brownish-red back surface fades into 

 the paler ventral surface; the inner rows are one on each side of 

 the middle line of the body. Except the first three or four 



rings of the head and the last one of the tail, each is provided 

 with four pairs of these bristles, so that in a full growu worm 

 of 150 rings there are between eleven and twelve hundred 

 walking organs. Each bristle has muscle attached to it, by 

 the contraction of which it is made to move forward and 

 backward, and thus the progression of the worm effected. 

 However, the animal is not entirely dependent upon these 

 organs for locomotion. On level surfaces progression is 

 effected chiefly by serpentine movements produced by the 

 contractions of strong lateral muscles. It is when the worm 

 climbs inclined and perpendicular surfaces that the bristles 

 come into play. That they are able to climb at such augles 

 is shown by the fact that they are often found in situations 

 which they could only have reached by ascending steeply in- 

 clined surfaces. Of course. I am here leaving entirely out 

 of account their ability to climb perpendicularly in their 

 holes. 



There is a popular notion that earthworms possess a re- 

 markable power of resisting mutilation; that a worm may 

 be cut into pieces and each piece will grow into a ne<v worm. 

 It is quite true that this animal is able to suffer the removal 

 of the posterior part of its body without any apparent per- 

 manent injury, but it is equally certain that if the anterior 

 portion be cut off both parts perish. In the anterior third 

 of the body are situated all the principal vital organs, the 

 stomach, liver, "brain" and reproductive organs. It is 

 certainly not to be supposed that a part of the body deprived 

 of these organs could maintain life. Probably any portion 

 of the body posterior to these organs can be removed without 

 destroying the life of the anterior part. 



I have just referred to the "brain" of the earthworm. It 

 is at least true that this humble animal possesses an organ 

 which is fairly comparable to the one which is highest and 

 chief est in the more advanced members of the animal king- 

 dom. It consists of two small oval-shaped masses of nerve 

 matter situated in about the fourth or fifth ring above the 

 alimentary canal. Each one gives off a nerve cord which, 

 encircling the alimentary tube, unite below in a ganglion 

 from which nerve cords are again given off to supply all 

 parts of the body. From the fact of its possession of a fairly 

 well developed nervous system it may safely be reasoned that 

 it gives the creature some pain when the sharp-pointed hook 

 is passed through its body. 



The organs of respiration in the earthworm are very curi- 

 ous. In each segment or ring is a pair of organs which, for 

 want of a better name, are simply called segmental organs. 

 They consist of greatly twisted tubes, one end of each of 



CROSS-SECTION OF EARTHWORM. 



c, cuticle; cm, circular muscle fibres; v. blood vessel; s, setae; cZ, 

 digestive canal; I »», longitudinal muscle fibres; b c, body cavity; n, 

 nerve trunk. 



REPRESENTATION OF EARTHWORM. 

 6, brain; p, pharnyx; n, nerve cbain; d, digestive canal; v, blood 

 vessel. 



which opens interiorly in the general body cavity, and the 

 other communicates with the external world through a pore 

 in the skin and cuticle. The microscope shows that these 

 tubes are lined with vibrating cilia and it is believed that by 

 their action currents of air and possibly water are made to 

 pass in and out of the body. In this way they are thought 

 to serve an office similar to that of the lungs in the higher 

 animals. 



Earthworms have no organs of vision, yet it is quite cer- 

 tain they are susceptible to light impressions. A simple ex - 

 periment proves this. If some worms be placed in a pot of 

 earth and taken into a dark room, after a time they would 

 come to the surface. If a bright light be then brought near 

 them they will speedily hide in the earth. It is thought 

 that the head region alone is susceptible to these impressions. 

 It is probable that from the two main nerve-masses , nerves are 

 given off to this part of the body which, in an imperfect way, 

 perform the office of the optic nerves in the higher animals. As 

 to the sense of hearing, these animals appear to be perfectly 

 deaf. They seem to take no notice of the loudest noises 

 made in their vicinity. It is true that if one stamps on the 

 ground near them they hastily retreat, but they are undoubt- 

 edly made aware of the jar through the sense of touch rather 

 than that of hearing. Their dullness in seeing and hearing 

 is partially made good by their extreme susceptibility to 

 touch. They are very sensitive to contact in every part of 

 their bodies. 



An interesting fact about these worms is that while each 

 animal is bi-sexual, producing both the male and female re- 

 productive elements, it is still necessary for fecundation that 

 two worms shall come together. A German naturalist, Von 

 Hensen,who has made these animals a subject of long study, 

 says that pairing takes place in the nigbt time in the months 

 of July and August. The worms cling to each other by 

 means of the thick saddle-shaped portion of skin situated 

 about a third of the way back from the anterior end of the 

 body. The young earthworm at birth is lise an old one ex- 

 cept that it is much smaller and consists of fewer rings. It 

 grows not only by the rings increasing in size, but also by 

 the addition of new ones. I do not remember to have seen 

 any statement as to their length of life. 



There are quite a number of species of earthworms, the 

 most noticeable differences being those of size and color. 

 There is one European species which attains a length of a 



foot and a half and is as large around as a man's little finger. 

 As far as I know, earthworms are found in all temperate and 

 tropical regions. 



At the approach of winter they go deep into their holes 

 and, passing into a dormant condition, remain until they 

 feel the warmth of the spring sun. According to the obser- 

 ver whom I have quoted above, their notes are sometimes six 

 feet deep. The deepest part is set with small stones, about 

 as large as a pin's bead, which are placed there by the worm 

 itself, and when such stones cannot be found small seeds are 

 used. "The delicate rootlets of plants also often run through 

 the whole length of the holes, forming beautiful webs along 

 the walls." 



It was thought by Darwin that these worms perform a very 

 important work in maintaining the fertility of the soil. He 

 calculates that "in many parts of England a weight of more 

 than ten tons of dry earth annually passes through their 

 bodies and is brought to the surface on each acre of land." 

 When it is remembered that the growth of plants is depend- 

 ent upon the supply of nitrogen contained in the surface soil, 

 and that when this element has been used up the soil can 

 regain it only by lying idle for a while, it is seen how im- 

 portant an office these worms serve in bringing to the surface 

 the rich subsoil and allowing the exhausted surface soil to 

 regain fertility. Besides this, it is probable that all soils, 

 even dry, sandy ones, are enriched by being passed through 

 their bodies. Then there is the fact that, by their constant 

 burrowing, the soil is rendered loose and porous, so that air 

 and water can get at the roots of plants. Darwin said, "It 

 may be doubted whether there are many other animals which 

 have played so important a part in the history of the world 

 as have these lowly-organized creatures." 



James Stouuer. 



THE AUDUBON SOCIETY. 



THE following account of the Smith College Audubon 

 Society was written by one of the lady professors of 

 the College for the Rutland Herald. It is in itself interest- 

 ing and is of value also as giving excellent suggestions for 

 the work of local Audubon everywhere; 



"About two mouths ago a few of the students of Smith 

 College felt that the time had come for some definite expres- 

 sion of the interest that had long been felt in the cause of 

 our native birds and for some organized effort for their pro- 

 tection. The history of the various conferences, committees 

 and meetings that resulted is not necessary; it is enough to 

 say that the students decided to form a Smith College branch 

 of the Audubon Society. 



"Enthusiasm for so righteous a cause could not but be 

 forthcoming and in abundance, but zeal should be according 

 to knowledge, which was conspicuously lacking. With the 

 best wills in the world, it soon became clear to the directors 

 of the society that only the merest beginning had been ac- 

 complished, when two-thirds of the students had given up 

 wearing birds on their bonnets, that the practical and theo- 

 retical bearings of the subject are by no means easy to get, 

 for unless one is near an ornithologist or a good collection, 

 it is very difficult to find out much about birds. 



"In view of these facts a careful subdivision of work was 

 clearly necessary to success. At the regular meetings of the 

 society, to be held once a month, the information of the 

 members will be constantly increased by lectures from men 

 w r ho have given time and skill to the study of everything 

 connected with birds — from their habits to the ethics of their 

 treatment by man — by papers setting forth the results of in- 

 vestigation or collation on the part of members themselves, 

 by the reports of the field work done among the members. 

 These regular meetings are thus to serve a double purpose, 

 in spurring the members on to new efforts and in recording 

 what has been accomplished. 



"A committee has been formed, to serve for one year, 

 having in charge the careful oversight of these meetings and 

 the making up of their programmes. They also appoint 

 other committees to take charge of the field work which is 

 organized, in general, as follows: Three parties are to set 

 out from the college on different days of the week, due notice 

 of the hour and destination being posted in some designated 

 part of the building. Each party is to be under the guidance 

 of a person sufficiently experienced in field work to be of 

 practical assistance to the beginners who may join the ex- 

 pedition. The work will consist of observation of birds, 

 efforts to learn their habits, song and distinguishing marks, 

 of the practical study of botany and meteorology, and in 

 short of that careful, discriminating tracing of nature's 

 workings that makes vital the dead words of text-book in- 

 formation. 



"The leaders of these parties will at first be obliged to in- 

 struct somewhat larger audiences than are convenient, but 

 it is believed that as the information is diffused, the parties 

 can break up into smaller groups, helping out their knowl- 

 edge by the use of keys and text books and gaining much 

 more freedom as regards time and strength. The leaders of 

 the parties will also teach the members efficient ways of re- 

 cording their observation and will see that the work is put 

 into proper shape for report to the society. 



"The main committee will have charge of whatever work 

 may seem practicable in the way of interesting the public in 

 any of the aspects of their subject. The circulars of the 

 Audubon Society, of the American Ornithologists' Union, 

 the numbers of Fokest and Stream, are fast enlightening 

 people's minds; but there remains a wide field for local 

 societies in interesting the children of public and private 

 schools, in teaching them to hunt birds 'without a gun,' in 

 making them increasingly intelligent and merciful. The 

 committee hopes to be greatly aided in its efforts by the 

 occasional presence of specialists who will accompany the 

 parties and direct their observation. With all these aids the 

 work will go on slowly at first, but it is believed that the 

 patience and industry will yield even richer returns here than 

 is their wont." 

 Smith College, Northampton, Mass., May 18. 



One Fool Commends Another. — The Lake Charles (La.) 

 Echo says: "Mr. R. A. Sibley, of Edgerly, is shipping about 

 2,500 bird skins per month to Newark, N. J. This is an in- 

 dustry which has lately been inaugurated in these parts, and 

 promises to be of some importance. Mr. Sibley ships the 

 skins of the jay, lark, snipe, crane hawk, owl, black and 

 other birds. The prices range from 5 to 13| cents each. Our 

 readers are aware that of late years bird feathers are being 

 used much more than formerly for trimming purposes, 

 hence the increased demand. As these buds are very de- 

 structive to the rice crops in injuring the stands, it is not 

 such wanton waste as it would be were they killed alone for 

 their plumes." 



