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THE POPULAR EDUCATOR 



trude from the outside. An American log hut is built much 

 after the manner of this peculiar kind of caddis tube, only 

 that by the backwoodsman the ends of the logs are notched 

 together and jointed, whilst by the worm the pointed spines 

 are united by glutinous silk, and caused to stand roughly out 

 most truly "like quills on the fretful porcupine;" and, fond 

 as fish are of the inhabitants of these spiked castles, few care 

 to risk being choked by interfering with them. Fig. 4 repre- 

 sents one of these spike-guarded dwellings. 



Stratagem, as well as the art of fortification, appears to be 

 brought to bear by other members of the ingenious family under 

 consideration. If we search carefully amongst the water-weeds 

 and lily-roots, we shall find some short thick cuttings of stout 

 grass blades, joined at the edges, perfectly green, fresh, and 

 as though snipped from the parent stem. Let us examine 

 them closely, and we shall find that within these fragments 

 of longitudinally-arranged grass blades is a tubular cavity, and 

 in it a worm of retiring habits, who withdraws his head to the 

 secret recess which he has formed for himself, and which no 

 fish of ordinary intelligence would look twice at. Fig. 5 repre- 

 sents one of these grass tubes. 



A search amongst the rough pebble stones will not unfre- 

 quently be rewarded by the discovery of a tiny trumpet-shaped 

 caddis tube composed entirely of minute particles of river sand. 

 A rare and beautiful example of this trumpet, or rather tusk- 

 like form of tube, is to be found in the British Museum ; it is 

 known as the Dentalium nigrum, from its tooth or tusk-like 

 form, and almost black colour. Fig. 6 represents one of these, 

 whilst Fig. 7 shows the more common tusk-shaped tube found 

 in most English rivulets and streams. We have found that 

 the period passed in the larvte or case-guarded stage varies 

 considerably with species, and the conditions to which specimens 

 are placed. Certain kinds manifest a marked partiality for 

 vegetable food, whilst others freely consume animal substances, 

 and will not hesitate to attack and destroy such weak and 

 helpless water-insects or small mollusks as may come within 

 their reach. 



Those of our readers who live sufficiently near to a river 

 or stream in which the caddis is found may without difficulty 

 capture a number of kinds by fastening five or six large 

 cabbage-stalks in a bundle, fixing a heavy stone at the bottom 

 to give weight to the mass, and then casting the lure into a 

 likely-looking pool in such a way that it may lie near enough 

 to the bank to be, at the end of three or four days, drawn 

 carefully and quietly out with a nook-ended stick. The worms 

 within their cases will then be perceived in considerable 

 numbers feeding on the cabbage-stalks. 



Such specimens as are required for either bait for fishing or 

 experimental purposes can be conveniently carried in a flannel bag 

 well moistened with clean water. Thin slices of cabbage-stalk 

 should be placed with the worms, and the bag dipped in water 

 once per day, and then hung in a cool, shady place to drain. 

 In this way the caddis may be preserved until it is placed in the 

 aquarium. Fig. 8 gives a diminished view of a caddis trap 

 prepared for throwing into the water. 



When about to pass from tha larva to the pupa stage, tne 

 worm proceeds to construct a sort of silk lattice-work or grating 

 over the mouth of its tube. This, although fine enough to 

 exclude intruders, admits of the free influx of water. Fig. 9 

 represents the worm on an enlarged scale after removal from 

 the tube, and Fig. 10 a cross section of a tube, showing the 

 form of reticulated work with which the mouth of a fagot-tube 

 is stopped when the worm is about to undergo the change 

 from larva to pupa : this view is also enlarged. About a fort- 

 night or three weeks pass before the silken net-work is broken 

 through by the pupa, which is represented on an enlarged 

 scale at Fig. 11. This quaint and curious-looking creature, on 

 quitting the case, struggles upwards to the surface, and is borne 

 onwards by the stream, until some friendly branch of river-side 

 tree, fragment of drift wood, or protruding rock, affords a 

 resting for the water-borne waif. Here, dried and warmed by 

 the spring sun, the pupa swells apace, becomes plump, and at 

 last, like the harlequin in the transformation scene of a panto- 

 mime, severs the fastenings of this sombre garment, casts it 

 on one side, and steps forth in all the pride of bright colours 

 and beauty of form. Fig. 12 represents the perfect insect or 

 caddis-fly, life size, after its change from the pupa stage ; and 

 Fig. 13 the insect with ita wings extended in the act of flight. 



No food of any kind is taken by the perfect insect during the 

 short period which passes between its birth, coupling, egg- 

 depositing, and death. 



Some of these flies swarm out abundantly during the day, 

 whilst others are nocturnal in their habits. Both the Perla 

 and Nemoura are at times confounded with the Phryganea, but 

 they differ materially from the insects we have been describing 

 in many marked respects. The common may-fly and stone-fly 

 of the river-side are familiar and well-marked examples of the 

 former families. Their larvaa do not construct cases in which to 

 dwell, are carnivorous feeders, and either dwell in small com- 

 munities amongst the hollow crevices of the river banks, or 

 beneath the ledges of stones and pebbles. From these lurking- 

 places they are at all times prepared to sally out for the purpose 

 of attacking any water-insect less powerful than themselves. 

 In every stage of their growth these insects afford vast quanti- 

 ties of nutritive and wholesome food for fish, and it is mainly 

 from the absence of this and similar larvas that many fish- 

 ponds and streams are found to be unprofitable and uncongenial 

 to the full development of the fish sought to bo propagated in 

 theml Other waters, although less promising in appearance, will 

 be found to contain insects of many kinds, and in these it will 

 bo found as a rule that fish not only rapidly increase in number, 

 but grow to a large size, and present to the eye of the angler 

 that sturdiness of form and brightness of colour which he knows 

 so well how to appreciate. The perfect insects of the Perla 

 and Nemoura families are remarkable for the long hair-like 

 spines or whisks which are attached to their tails. The latter 

 shortly lose these forked appendages, but the former retain 

 them during their short lives 



The term eplwmera has been applied to the family of may-flies. 

 Ephemeral, too, are many of the fleeting joys and triumphs of 

 human life. Hatched in the first rays of an early spring morn- 

 ing, the may-fly finds a partner and deposits its eggs before 

 the sun sets, and, ere another sunrise, ceases to exist. It has 

 been stated, on the authority of Reaumur, that it sometimes 

 happens in the south of Europe that the bodies of dead ephemera 

 cover the ground in such countless myriads as to lead to their 

 being carted away for manure by the farmers of the neighbour- 

 hood through which the rivers watering the district flowed. 



LESSONS IN LATIN. LIII. 



GOVERNMENT OP THE CASES. 



IF we look at the cases according to their applications, we find 

 that the nominative (Latin, nomen, a name) is that case in 

 which the name or noun stands when it is uninflected, and when 

 it is the subject of the verb. The nominative answers to the 

 question who ? or rvhich ? as 



Naso dixit; quis? Naso. 



Naso said, (it) ; who (said it ?) Naso. 



The genitive (from gigno, I beget; genus, a kind or race) 

 denotes the origin of a person or thing ; as 



Patris filia est pulchra, the father's AavgUer is fair ; 



and hence possession in all its varieties. The genitive answers 

 to the question whose ? as 



Est matris domas ; cujus ? matris. 



It is the mother's house ; wliose ? mother's. 



The dative (from do, dare, datum, I give) conveys the ideas 

 implied in our to and for, and so is the case of giving or re- 

 ceiving. The dative answers to the question to or for whom ? 

 as in this example : 



Datur equus militi ; cui ? militi. 



A horse is given to a soldier ; to wlwm ? a soldier. 



The accusative (ad and causa) is the case of that which is 

 caused or affected more strictly, that which is affected that 

 is, affected by the verb ; that which is the object of the verb's 

 action. As denoting the objecb, this case is more significantly 

 called in English the objective case. The accusative or objec- 

 tive case answers to the question whom ? or what ? as 



Misit Robertum ; quern ? Robertuxn. 



He sent Robert; whom? Robert. 



The vocative (voco, I call) is the case of calling that is, of 

 invocation or direct address ; as 



Veni hue, do mine. Sir, come hither 1 



