WORMS. 



59 



worms, and may readily be found in the rich, moist humus of the woods, 

 where they are seen as little white threads, rarely reaching an inch in 

 length. Of our American species almost nothing is known, though we 

 have them in the greatest abundance. Should the reader wish to study 

 them, he can follow the process adopted by Anton Schneider in studying- 

 the European species. He took a pot with a lot of earth in it and poured 

 in a little blood or milk and kept the whole moist. The earth was filled 

 with eggs and embryos, and these speedily made their way to the putrefy- 

 ing milk or blood and there attained maturity. 



Of the aquatic forms and their allies mention need be made of but two 

 types. One is comparatively abundant in pure cider vinegar and is. 

 known as the vinegar-eel ; the other is occasionally found in stale paste 

 and is known as the paste-worm. These worms are less than a tenth of 

 an inch in length 



and so transparent 

 that, under the mi- 

 croscope, the whole 

 of their anatomy 

 stands revealed. 

 The paste-eel has 

 lately come to the 

 front as an aid to 

 play a part in a 

 fraud. Traveling 

 vendors of so- 

 called microscopes 

 declare that their 



Fig. 58. — Vinegar-eel (Leptodera). 



worthless instruments will show " the animalcules in water," and to prove 

 it they show these paste-eels. As described b}^ Dr. James, they take a drop 

 of perfectly clear water with a toothpick and place it on a glass, but the 

 toothpick has previously been dipped in sour paste filled with the worms. 

 No wonder the would-be purchaser sees "animalcules'' in abundance. 



The parasitic forms are more important than the free-living forms. 

 First to be mentioned of these is that dread of all travelers in the tropics 

 of the Old World, especially on the west coast of Africa, — the famous 

 Guinea-worm. Of its history but little is known. In some way the young 

 obtains a lodgment under the human skin, usually of the feet or legs, and 

 there grows to an enormous length. It forms a bad ulcer, and in the 

 centre of the sore appears the head of the worm. The process of extrac- 

 tion is difficult, and if great care is not exercised, one of extreme danger; 

 for if the delicate animal be broken, the eggs which it contains will remain 



