ON AVIAN CESTODES. 429 



33. Contributions to the Anatomy and Systematic Arrange- 

 ment of the Cestoidea. By Fkank E. Beddard, M.A., 

 D.Sc, F.R.S., F.Z.S., Prosector to the Society. 



[Received and Read Maj- 25, 1915.] 

 (Text-figures 1-6,) 



XYII. On Tjenia tauhicollts op Chapman and on the 



Genus Chapmania. 



Index. Page 



Structure of Chapmania tauricollis 430 



Systematic position of C. tauricollis 439 



Genera of Idiogeninse 441 



I obtained, on June 30th, 1914, a large number of examples of 

 ■Cestodes from an nAmerican Rhea {Rhea americana) which died 

 in the Society's Gardens on the previous day. All these worms 

 were found in the right csecum, and none of them in the small 

 intestine. As is known, the cajcum is very rarely found to be 

 inhabited by Oestode parasites, though there are cases on 

 record *. 



From this bird three species of Cestodes have been described. 

 Of these three, Gittotcenia rhece may be set aside at once as having 

 nothing in common with the species which forms the subject of 

 the present remarks. This latter species is identical with either 

 Tcenia tauricollis oi Chapman or Tcsnia struthionis Houttuyn 

 ■among those which have been found in Rhea, or is another 

 species altogether. Tcenia taioricoUis has been placed in a genus 

 Chapmania (which is not widely different from Idiogenes), while 

 Tcenia struthionis is now assigned to Davctinea. In spite of this 

 generic separation, which depends upon the not at all full descrip- 

 tion of Davcoinea stritthionis by Parona f and von LinstowJ, I 

 am by no means certain that they are not actually identical 

 ■at least generically, 



Davainect struthionis, though found in the Ostrich, is stated by 

 Fuhrmann § to occur also in Rhea americana ; but the statement 

 of Fuhrmann is not advanced Avith absolute positiveness ; and it 

 is only a statement in that no characters of Davcmiect struthionis 

 are given by him to confirm the identification. The fullest account 

 of the structure of Dccvccinea struthionis is that of v. Linstow. 

 Parona's notes give no anatomical detail to speak of. It is prob- 

 ably therefore to the former paper that the responsibility for 

 including this species in the genus Dcovainea by all subsequent 



* See Bronn's ' Thier-Reich,' Bd. iv. Abtli. 1 b, p. 1625. 



t Ann. Mus. Civ. Genova (2 a) ii. 1885, p. 425. 



X Arch. f. mikr. Anat. xlii. 1893, p. 447. 



§ "Die Cestoden der Vogel," Zool. Jalirb. Suppl.-Bd. x. 1908, pp. 6 and 19. 



30* 



