310 DR. T. S, COBBOLD ON HUMAN ENTOZOA. [NoV. 25, 



Cruveilhier, Curling, Portal, Foster, Thompson, Annesley, Keber, 

 Virchow, Aran, Vogel, Lebert, Major, Livois, Thiel, Moquin-Tan- 

 don, Davaine, &c. 



E. veterinorum, Rudolphi, Bremser, Blainville, Gurlt, Allessan- 

 drini, Owen, Dujardin, Gervais, Leuckart, Huxley, Weinland, &c. 



E. scolicipariens, Kiichenmeister. 



E, altricipariens, Kuchenmeister, Cobbold. 



E. polymorphus, Diesing, Leidy. 



E. granulosus, Rudolphi. 



E. simicB, Rudolphi. 



E. giraffes, Gervais. 



Polycephalus hominis, Goeze, Jordens. 



P. humanus, Zeder. 



P. granulosus, Zeder, Cloquet. 



P. ecMnococcus, Zeder, Tschudi. 



Acephalocystis, Laennec, Diesing, Dujardin, Nitzsch, Sieboldj 

 Van Beneden, Moquin-Tandon, &c. 



A. ovoidea, Laennec, Cloquet, Deslongcbamps, Chiaje. 



A. granulosa, Laennec, Cloquet, &c. 



A. surculigera, Laennec, &c. 



A. endogena, John Hunter, Owen. 



A. escogena, Kuhl. 



A. macaci, Cobbold. 



A. ovis tragelaphi, Cobbold. 



Vesicaria granulosa, Schrank. 



Hydatigena granulosa, Batsch. 



Hydatis, Liidersen, Rudolpbi, Olfers, Bremser, Leuckart, Kuhn, 

 Tscbudi, Dujardin, Wilson, Rokitansky, Moquin-Tandon, Barker, 

 Davaine, &c. 



H. erratica, Blumenbacli. 



Following Kuchenmeister, Weinland and others suppose that 

 there are two distinct forms of EcMnococcus severally referable to 

 different Tapeworms, one of which is on all hands admitted to be 

 Von Siebold's Tcsnia ecMnococcus, the other an unknown Tcenia, 

 also supposed to infest dogs. That EcMnococci vary much, both in 

 regard to the number of cephalic hooks they display at certain in- 

 tervals of growth, and also in respect of the mode of evolution of the 

 scoleces, few will deny ; but, according to Leuckart, we are not there- 

 fore warranted in accepting Kiichenmeister's view as to the specific 

 distinctness of certain forms. Like others, I had been led away by 

 Kiichenraeister's authority, although I have had abundant opportu- 

 nity of investigating these singularly interesting larvae. The grounds 

 on which. Leuckart disputes Kiichenmeister's view are, I think, per- 

 fectly satisfactory ; for he shows conclusively that the proportional 

 number of hooks fluctuates in both forms, whilst the alleged differ- 

 ences in the size and character of the hooks themselves have reference 

 to their degree of development (' Die menschlichen Parasiten,' p. 328 

 ef seq.). If this view be generally accepted, it cannot fail to suggest 

 important hints as to the best mode of checking that formidable 



