20 



NATUKAL SCIENCE NEWS. 



in various parts of the world — as 

 America, Russia, Hungary, Spain, 

 Portugal, in the marshy plains of 

 Egypt, and in various parts of 

 Asia. It belong to the class (znne- 

 lides, or ringed worms, its body be- 

 ing composed of a series of rings, 

 or circular muscles, by the succes- 

 sive contraction of which it moves 

 along either in the water or upon 

 the surface of leaves, reeds, or 

 other solid bodies. The tail ex- 

 tremity is in the form of a cup or 

 sucker, by which it adheres firmly 

 to flat substances, on the same 

 principle as a boy's leather sucker 

 adheres to and lifts up a stone. 

 The mouth is also in the form of a 

 sucker, and is, moreover, furnished 

 with three cartillaginous teeth, 

 placed so as to form with each 

 other a triangle. When examined 

 and felt with the point of a finger, 

 they seem soft and blunt; but the 

 animal, when about to pierce the 

 skin, seems to have the power of 

 erecting them into firm, sharp- 

 edged lancets, which saw through 

 the integuments in a single instant, 

 and almost without inflicting any 

 pain. Having made the puncture, 

 the blood is extracted by a process 

 of suction, and is passed through 

 the ceophagus into the stomach, or 

 rather stomachs, of the animal, 

 which consist of a series of com- 

 municating cells, that occupy the 

 greater part of the interior of its 

 body. The leech having thus gor- 

 ged itself to the utmost, if undis- 

 turbed, remains in a half-torpid 

 condition till it has digested its 

 gory meal, and not unfrequently 

 dies of the surfeit. If it survives 

 it will be greatly increased in size. 

 They can live for months and years 

 on what appears to be pure water 

 alone. This forms the singular 

 circumstance in the diet of these 

 animals. They delight to gorge 

 themselves with a full meal of 

 blood, even to surfeit; and yet 

 with plain water they live, grow, 

 and seem to have the greatest en- 

 joyment of existence. It would 

 appear as if their three lance- 

 formed teeth, and their carniverous 

 appetites, were bestowed more for 

 the benefit of man than for them- 

 selves, and that, in their system of 

 dietetics water is the rule and blood 

 the exception. 



The medicinal leech is a native 

 of many parts of Britain, but is 

 now becoming very rare. France 

 is supplied chiefly from Strasburg, 

 whence they are imported from 

 Hungary, Turkey, Wallachia and 

 Russia, and kept in ponds. They 

 are carried into France on spring 

 wagons, and are contained in mois- 



tened bags, each bag containing 

 120 leeches. Previous to 1834 up- 

 wards of 46,000,000 of leeches 

 were imported into France annual- 

 ly. At present the numbers have 

 decreased to 17,000,000. They 

 are imported into London and 

 Leith by sea, packed in little bags, 

 which are occasionally moistened 

 with water during the short voy- 

 age. In general they arrive fresh 

 and healthy; but they are not un- 

 frequently liable to disease, which 

 destroys great numbers. There 

 are three sorts, or sizes, the largest 

 and middle sorts being reckoned 

 the best. A large leech is calcu- 

 lated to abstract half an ounce of 

 blood, besides the quantity which 

 .flows from the wound afterward. 

 The smaller sizes are comparative- 

 ly inefficacious. 



A common animal in the pools 

 of this country is the horse leech. 

 It nearly resembles the other, but 

 is of a more uniform color, and not 

 so decidedly marked with greenish 

 streaks on the backs as the medici- 

 nal species. The horse leech has 

 no great inclination to fasten on 

 the human skin, but when it does 

 so it takes its fill, just like the 

 other, and no more, There is a 

 popular but unfounded belief that 

 if a leech of this description do 

 fasten on the skin, it will continue 

 to suck and discharge the blood 

 till every drop in the body is ex- 

 hausted. Hence they are the 

 dread of every school boy who 

 happens to wade with naked legs 

 into their dominions. 



The leech, like many other ani- 

 mals, appears to have a very nice 

 sensibility in regard to atmospheric 

 changes, and especially what re- 

 gards the electric modifications of 

 the air. Before storms, or any 

 sudden change in the atmosphere, 

 the leech is seen in great activity, 

 and darting up to the surface of 

 the water in its jar. These ani- 

 mals, too, at certain times, are 

 found to move out of the water, 

 and remain for a considerable pe- 

 riod clustered on the dry-upper sur- 

 face of the jar; while on other oc- 

 casions they will remain for days 

 immersed in the water near the 

 bottom. They produce small eggs, 

 which form into cocoons, from 

 which in due time the living young 

 make their appearance. 



Geology and the "King Crab." 



"Visitors to the Aquarium House 

 at the Zoological Gardens have no 

 doubt noticed the living specimens 



of that curious creature, the "king 

 crab, "which are now in a tank 

 alive and well. The most curious 

 part of their structure is the eyes; 

 they have four, which are com- 

 posed of numerous lenses, like the 

 dragon-fly or bee, and are so ar- 

 ranged that they can see objects 

 on each side of them. Besides be- 

 ing interesting simply as living 

 creatures, king crabs are the near- 

 est existing relations to the ancient 

 form of beasts called 'trilobites. ' " 

 — The London Field. 



The king crab is what is com- 

 monly known here as the "horse- 

 shoe." Such creatures' are taken 

 by thousands annually on the 

 marshy coasts of New Jersey and 

 Long Island, and are used exten- 

 sively for manuring the land. No 

 living specimens are now found in 

 England, but their fossils are uot 

 uncommon. The past geologic 

 age of Europe is similar in many 

 of its features to the present in the 

 New England States. Hugh Mil- 

 ler in his lecture on geology says: 

 "America though emphatically the 

 A T ew World in relation to its dis- 

 covery by civilized man, is at least 

 in these regions an old world in re- 

 lation to geological type; and it is 

 the so-called Old World that is in 

 reality the new one." 



Professor Agassizsays: 



"If we compare a list of the fos- 

 sil trees and shrubs from the terti- 

 ary beds of GZningen with a cata- 

 logue of the trees and shrubs of 

 Europe and North America it will 

 be seen that the differences scarce- 

 ly go beyond those shown by the 

 different floras of those continents 

 under the same latitudes. But 

 what is quite extraordinary and un- 

 expected is the fact that the Euro- 

 pean fossil plants of that locality 

 more closely resemble the trees 

 and shrubs which grow at present 

 in the Eastern parts of North Am- 

 erica than those of any other part 

 of the world. The present East- 

 ern American flora and fauna have 

 a more ancient character than those 

 of Europe. The plants, especially 

 the trees and shrubs growing in 

 our days in the United States, are 

 as it were, old-fashioned." 



On this topic Hugh Miller again 

 says: 



"Towards the close of the mio- 

 cene period old Scotland exhibited 

 features greatly resembling those 

 presented to the Puritan fathers by 

 the forest-covered shores of New 

 England, little more than two cen- 

 turies ago. — Scientific American. 



