Dr. O'Bryen Bellingham on Irish Entozoa. 317 



of Yorkshire,' vol. ii. pi. 5. fig. 5 : externally it closely resembles 

 another species which I consider the same as Dr. Morton's fossil re- 

 presented in Silliman's Journal, vol. xxix. pi. 26. fig. 37, and which 

 is from the carboniferous rocks of Northumberland ; but the direction 

 of the cartilage fulcra, as already noticed, is very different in each. 



I have little doubt of the fossil to which Mr. J. de C. Sowerby has 

 applied Fleming's name Unio Urii (Brit. Animals, p. 417) being quite 

 distinct from the shell so called, and a true Allorisma. In this case 

 the specific name which Mr. Sowerby has given to the former may 

 be retained, unless this fossil should hereafter be considered as a va- 

 riety of Allorisma elongata. 



XXXVIII. — Catalogue of Irish Entozoa, with observations. By 

 O'Bryen Bellingham, M.D., Fellow of and Professor of 

 Botany to the Royal College of Surgeons in Ireland, Member 

 of the Royal Zoological, Geological and Natural History So- 

 cieties of Dublin, &c. 



[Continued from p. 256.] 



Genus 18. Taenia. 



(Derived from raivia, vitta.) 



Gen. Char. — Body long, flat, soft, and composed of a great number 

 of distinct articulations. Head in general larger than the neck, 

 furnished with two pairs of oscula, suckers or discs, and often with 

 a rostellum or prominence in front, which is surrounded or not 

 by one or two circles of recurved hooks ; — what Rudolphi terms 

 ' armed.' 



The species of this genus have been hitherto found in the bodies 

 of vertebral animals alone, and the alimentary canal is the only 

 part which they are found to inhabit ; they usually occur in the 

 small intestines. They are most abundant in birds, next in mam- 

 malia, then in fish, and lastly in reptiles. Rudolphi enumerates 

 146 species in his ' Synopsis/ of which 53 are doubtful. 



The term Taenia was employed by the ancients, but they neces- 

 sarily confounded the genus Bothriocephalus with the Taenia. The 

 digestive apparatus of these animals consists of two straight late- 

 ral canals of the same diameter throughout, which commence at 

 the oscula of the head, run backwards parallel to one another, 

 close to the margins of the articulations, and communicate with 

 one another by a transverse branch at the posterior edge of each 

 articulation. 



The organs of reproduction are more complicated; we find 

 male and female organs not only in every individual, but in all 

 the larger articulations of the same individual. A small papillary 

 projection is seen near the centre of the margin of each articu- 



