48 ZOOLOGY. 



2. GordiidcE. The genus Filaria is long, slender, thread-like, and smooth, 

 with a somewhat rigid texture, and many species are found in various 

 animals, including insects and mollusca. Filaria raedinensis {pi. 77, ßg. 43), 

 the guinea worm, infests the muscles and subcutaneous tissues, chiefly 

 of the lower limbs, in Arabia, Upper Egypt, AVest Africa, and the West 

 Indies. It is sometimes located about the eye, and beneath the tongue ; and 

 occaftionally it makes its way to the surface of the body, causing a sore, 

 from which it may be extracted if a little is withdrawn daily, care being 

 taken not to break it, as in that case the inclosed part remains and causes 

 inflammation, which may render amputation necessary. A sailor, who 

 frequently met Africans on shipboard with sores caused by the worm, had 

 been on shore in AVest Africa for three hours barefoot, having himself a 

 small sore on the thigh at the time. He arrived in England in October, 

 1843 ; and in the middle of the subsequent May a sore appeared on the left 

 instep, which finally opened and disclosed part of a white worm, about the 

 size of a violin string, of which five inches were cut oft'. This was succeeded 

 by violent inflammation and suppuration upon the foot and leg, until the 

 remaining two feet and a half of the worm came away. On the 23d of May 

 another sore appeared upon the left fore-arm, disclosing a second fllaria, 

 which was gradually and carefully removed in fourteen days, and found to 

 be thirty-two inches long. A third could then be felt under the integument 

 of the right foot. This species attains a length of six feet, and is said to be 

 sometimes seen swimming in the water of the countries it inhabits. 



Filaria j^aßillosa {fig. 45) is found in the abdomen, chest, and eyes of 

 the horse. Dr. Charles A. Lee gives a figure of it in the Am. J. Sei., 1840, 

 vol. xxxiv. p. 279. He states that it is from one to seven inches long, and 

 one third of a line in diameter. The specimen seen by him seems to have 

 irrown from half an inch to about four inches in four months. 



Filaria plialangii {pi. 77, fig. 62) has been found in Phalangium 

 cornutum. 



Filaria li/cosa', Hald. Pale-reddish when recent ; flavous when dried by 

 heat ; rigid, smooth, and shining, slightly tapering towards one end ; about 

 five inches long, and one millimetre in diameter at the largest end. Found 

 in Eastern Pennsylvania, in a specimen apparently of Zycosa scutulata, 

 Hentz, ten lines long, and, when the size of the spider is considered, a 

 remarkably large species. The specimen being much contorted, and one 

 end still within the spider, the i)recise length could not be determined. 

 Fig. 43 raiglit pass for a representation of it, and the spider is a little larger 

 \.haj\fig. 37" m pi. 78. 



The genus Gordius is found free in water, or as an internal parasite. 

 Gordius aqvaticvs is found under all these circumstances, as it has been 

 ascertained to infest insects. Tliese worms resemble a thin thread or 

 stout hair, and being seen in running water, or in puddles along roads, 

 particularly after rain (see Mag. Nat. Hist., 1836, pp. 9, 241-2, 355), they 

 are popularly supposed to be metamorphosed horse-hairs. They are male 

 and female, oviparous, and have a more complicated organization than their 

 external simplicity might be supposed to indicate. 

 252 



