68 AVIAN CESTODES, 



pores alternating irregularly : sex-ducts passing between the 

 excretory vessels ; testes situated at the posterior end of the 

 segment; uterus sac-like. He goes on to state*, amongst 

 other things, that Ghoanota'nia infundihnlnm had been 

 shown, by Cohn and by Clerc, to possess characters which he 

 regarded as sufficient to justify its inclusion in his genus 

 Mono-pylidium, the type of which is M. musculosum Fuhr- 

 mann. He, therefore, considered that a new type shovxld be 

 taken for Choanotcenia, and selected C. (jdlhulce Zeder. 

 Railliet and Henryf then pointed out that, if the type of 

 Clioanotwnia possesses the features of the more recently 

 erected genus MonopyUdiuui , then the latter must be a 

 synonym of the former. Moreover, a type-species, when 

 once designated for a genus, cannot be replaced by another 

 in that genus. They then proposed the name Icterotitnia for 

 the remaining species included by Fuhrmann in his genus 

 Moiiopylidium. 



Ransom| has recently given a summary of the discussion, 

 but he has retained both CJiotniotcntia and JIoiiojJi/lidiuDi, 

 though he has given a fuller diagnosis of the former. His 

 i"eason for maintaining both genera is that, in the former, 

 true egg-capsules do not occur, as far as is known ; whilst in 

 the latter genus, they do. He therefore restores T. infundi- 

 hidum to Cltoaiiotitnia, but leaves the other species in 

 Mono'pylidiuui. As he had studied G. infinulibulum in 

 detail ||, he has been able to give a more extended diagnosis 

 of this genus 51 the following details being either substituted 

 for, or added to, some of those given above: — Genital pores 



* Fuhrmann, 0., I.e., p. 54, p. 66, footnote. 



t Railliet, A., and Henry, A., " Les Cestodes des Oiseaux," Rec. Med., 

 Vet. Paris, Ixxxvi., 1909, pp.337-8. Quoted by Ransom, B. H., "The 

 Tfenioid Cestodes of North American Birds." Bull. 66, U. S. Nat. Mus., 

 1909, p.74. 



J Ransom, I.e., p.74. 



II Ransom, Ann. Rep. Bur. Animal Industry, xxi., 1904(1905), pp.277-78. 



^ Ransom, Bull. 69, U. S. Nat. Mus., 1909, p.74. 



