170 



ZOOLOGY. 



while the male is unknown. The worm lives in the con- 

 nective tissue under the skin, especially of the extremities. 

 As the body of the female is full of young, the worm has to- 

 be carefully and slowly extricated, so as not to be broken and 

 cause the embryos to be scattered under the skin of the host. 

 Carter regards a small worm ( Urolales palustria] frequent in 

 brackish water, as the immature form of the Guinea-worm. 

 It is also believed that the embryos enter the bodies of water- 

 fleas (Cyclops, etc.), and there moult, and that consequently 

 they may be introduced into the body by drinking standing 

 water ; but this bus not been proved. Other species live in the 

 peritoneum of the horse and apes, and an immature species 

 (Filar la lent is) has been found in the lens of the human 

 eye. Filaria sanyuiuis-lwminis is a worm of microscopic 

 size found living in the blood of the mosquito in India and 

 China. It is said that the eggs are swallowed in the water 

 drunk by man, are hatched in his intestines, and obstruct 

 the smaller blood-vessels, causing, it is claimed, various 

 forms of elephantoid disease, perhaps even leprosy. The 

 mosquito sucks up the parasite in the blood of leprous pa- 

 tients, voiding the eggs in the pools it frequents. Filaria 

 hematica has occurred in the blood of the foetus of a dog 

 whose heart was tilled with them. Ears of wheat are 

 often infested by a minute Xematode (Tylenchus zcundens 



Schneider, Anyuil- 

 lula tritici of Need- 

 ham, Fig. 118). 

 Other species live in 

 flowers, moist earth, 

 and sour decaying 

 substances. Anyuil- 

 lula aceti Ehren- 

 berg is from one to 

 two millimetres in 

 length, and lives in 

 vinegar. 



The genus Chato- 

 soma lives free in 

 the sea, and has a broad swollen head beset with fine hairs. 

 It apparently connects the true Ncmatodes with Sagitta. 



Fig. 118. Young Wheat-Worm, greatly magnified. 

 a, section of'chciit" ex I Hinting some worm? and multi- 

 tudes of eggs, magnified : ft, an ngg containing a worm 

 ready to liatch. From Curtis, after Bauer. 



