180 PARASITES OF MAN 



expelled per anum in the immature condition in which they first 

 escape from the body of the parent worm. It further appears 

 that, after their expulsion, a period of six months must elapse 

 before embryonic formation commences. The fully-developed 

 embryo measures g" in length, and resembles the parent to a 

 certain extent. 



Whipworms rarely put their bearers to inconvenience; never- 

 theless, both human and animal hosts occasionally suffer from 

 their presence. Thus, Felix Pascal quotes a remarkable and 

 fatal instance of cerebral symptoms from this cause in a girl of 

 four years of age ; and Mr Gibson has recorded an instance in 

 which these worms produced paralysis and loss of speech. 

 According to Professor Axe, sheep suffer severely from the 

 allied species. 



BIBLIOGRAPHY (No. 22). Bastian, H. C., " On the Anatomy 

 of the Nematoids," ' Phil. Trans./ 1866, p. 54,5.Bellingham, 

 0. B., " On the frequency of Trichocephalus dispar in the 

 Human Intestines/' ' Rep. of Brit. Assoc., in Dubl. Journ./ 

 1838, and in ' Med. Chir. Revi/ 1838; see also Bibliog. No. 33 

 (and the biography of Bellingham by Dr Mapother, in ' Dubl. 

 Jrn. Med. Sci./ 1877, p. 471). Busk, G., " Anat. of T. dispar;' 

 'Ann. Nat. Hist./ vol. vii, 1841. Chioje, sul Tricocephalo 

 disparo, &c., 1836.- Colloid, ' Entozoa/ pp. 69 and 329. 

 Idem, ' Worms/ pp. 31 and 67. Davaine, 1. c., p. 205. Idem, 

 ' Compt. Rend./ 1858, p. 1217, and 'Journ. de Physiol./ 1859, 

 p. 296. Dubini, ' Entozoografia umana/ p. 83. Dujardin,}. c., 

 p. 32. Eberth, " Die Generationsorgane von T. dispar," 

 f Sieb. und Koll. Zeitschr./ 1860, s. 384. Gibson, D., " On a 

 Case of Paralysis, with loss of speech, from intestinal irrita- 

 tion (produced by T. dispar), ' Lancet/ Aug. 9th, 1862, p. 

 139. Goeze, ' Naturg./ s. 112. Gurlt, 'Path. Anat./ p. 350. 

 Kuchenmeister, 1. c., s. 235 ; Eng. edit., p. 321. Leidy, ' Proc. 

 j^.cad. Phil.,' viii, p. 53.-*-Leuckart, 1. c., s. 465. Mayer, Sieb. 

 und Koll. ' Zeitsch. f. wiss. Zool./ Bd. ix, s. 367 ; Bd. x, s. 233, 

 and s. 383, 18S8-60. Herat, 'Diet. Sc. Med./ p. 560. Von 

 Siebold, 'Wiegm. Arch./ 1845. Wilson, E., 'The Veterinary 

 Record and Trans.,' vol. ii, p. 47, 1846. 



Filaria Bancrofti, Cobbold. The history of the discovery of 

 this entozoon is second only in interest to that of Trlchnm 

 spiralis. Step by step the facts have been evolved by a slow 

 process of observation, and from the data thus afforded a toler- 

 ably connected narrative of the probable life-cycle of this 



