1862.] DR. T. S. COBBOLD ON HUMAN ENTOZOA. 297 



mystax. In conclusion, therefore, I would assure all medical gentle- 

 men who may meet with cases of Ascarides that they would confer on 

 entozoologists a favour, and on science an advantage, if, when in any 

 doubt as to the specific character of these or other parasites, they 

 would kindly submit them to the scrutiny of those who are intimately 

 conversant with the science of helrainthology*. 



12. Trichocephalus dispar, E-udolphi. 



T. dispar, Rudolphi, Bradley, Cuvier, Bremser, Chiaje, Belling- 

 ham, Mayer, Busk, Siebold, Dujardin, Tutschek, Pruner, Wedl, 

 Diesing, Kiichenmeister, Leidy, Moquin-Tandon, Eberth, Cobbold, 

 Weinland, &c. 



T. hominis, Goeze, Schrank, Gmelin, Rudolphi, Jordens, Brera, 

 Lamarck, Blan chard. 



T. simicB patas, Treutler. 



T. lemuris, Rudolphi. 



T. palceformis, Rudolphi, Dujardin. -• 



Ti'ichuris, Buttner & Rcederer, Wagler, Bloch. 



Ascaris trichiura, Linnseus, Miiller, "Werner. 



Few of the entozoa have excited more interest than this species, 

 partly owing to the angry discussion which its discovery inaugurated, 

 and partly on account of its singular and elegant whip-like appear- 

 ance. The original name of Trichuris, given to it 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 generally thought to be scarce in England — a persuasion which 

 has probably arisen from the negligence of pathologists, whose ardu- 

 ous duties connected with the superintendence o^ post mortem exami- 

 nations have perhaps left them little time for these inquiries f. 



On the other side of the Channel this worm is so abundant in some 

 localities that Mons. Davaine calculates that not less than one-half 

 of the inhabitants of Paris are infested by it. The general organiza- 

 tion of Trichocephalus has been well investigated, more particularly 

 by Mayer, Siebold, Dujardin, Blanchard, Kiichenmeister, and Eberth; 

 but (as I have recently shown in my third memoir on " Entozoa," 

 published in the Linnean Society's 'Transactions') the statement of 

 Kiichenmeister that there are no external appendages in the female 

 of Trichocephalus comparable to those known to exist in the allied 

 Trichosomata is incorrect. In connexion with these organs I have 

 also endeavoured to throw light upon the conflicting statements of 

 Mayer and Eberth, and I have demonstrated more fully the very 



* Since writing the above, with great good fortune and most opportunely, a 

 third case has been brought under my notice, — Dr. Lankester, F.R.S., having very 

 kindly placed in my hands, last Thursday evening (Nov. 20), a nematode sent to 

 him by Mr. Scattergood, of Leeds. This worm is A. mystax, from a child only 

 thirteen months old, whose case I hope shortly to lay before the medical profes- 

 sion. I now exhibit the parasite to the Society. (See ' The Lancet' for Jan. 10, 

 1863, p. 31, where the case has since appeared. — T. S. C.) 



t To Dr. Rutherford Haldane, F.R.C.P., Physician and formerly Pathologist to 

 the Royal Infirmary of Edinburgh, I am indebted for several perfectly fresh ex- 

 amples of this worm. 



