NEMATODA 179 



is curved, and emits at the extremity a short, tubular penis- 

 sheath, armed with minute retroverted spines. The tail of the 

 female is straight and bluntly pointed. The eggs measure 5^" 

 to ~" in their long diameter. The whipworm infests the 

 cascum, and also the upper part of the colon. Upwards of one 

 thousand were found by Kudolphi in a woman. 



The original name of Trichuris, given to this worm by 

 Buttner, could not, of course, be allowed to stand when it 

 became evident that the so-called tail was in reality the head 

 and neck. The Trichocephalus is not uncommon in England 

 and Ireland. It is less frequent in Scotland. On the 

 continent, however, it is so abundant that M. Davaine calcu- 

 lates that not less than one half of the inhabitants of Paris are 

 infested by it. From what Dujardin has said it can be 

 scarcely less abundant in Northern France, for M. Duval, the 

 distinguished director of the Eennes School of Medicine, 

 supplied that helminthologist with numerous specimens on 

 various occasions. The worm abounds in Italy and Egypt ; 

 being scarcely less prevalent in the United States. The 

 lamented Mr Noel, one of my old pupils at the Middlesex 

 Hospital College, brought me specimens which he found post- 

 mortem on three or four occasions. Dr Haldane, of Edinburgh, 

 once or twice obtained large numbers (post-mortem). In 

 Ireland, Bellingham found the worm in eighty-one out of ninety 

 post-mortem examinations. Mr Cooper, of Greenwich, met 

 with it, post-mortem, in eleven out of sixteen instances. When 

 treating patients for tapeworm I have repeatedly expelled the 

 whipworm. 



The organisation of Trichocephalus dispar has been investi- 

 gated by Dujardin, Mayer, Yon Siebold, Eberth, Bastian, and 

 others. Prof. Erasmus Wilson and myself have carefully 

 studied the anatomy of the closely-allied whipworm of ruminants 

 (T. affinis) which is discussed in my ' Entozoa/ 



The statement of Kiichenmeister that there ,re no external 

 appendages in the female Trichocephalus comparable to those 

 known to exist in the allied Trichosomata, is incorrect. Leuc- 

 kart's, and especially Virchow's, researches disproved Kiicheii- 

 meister's and Meissner's notion that Trichina were the young 

 of Trichocephalus. The experiments of Davaine render it 

 probable that the young get into the human body in a direct 

 manner. He finds that the eggs undergo no development 

 whilst yet lodged within the host's intestines. The eggs are 



