314 



Ctsticeecus of Taenia liophallus. 

 By T. B. Rosseter, F.R.M.S. 



(Read November 20th, 1896.) 



Number of hooks, 10 ; length of hooks, 0035 mm. ; a-b, 0*007 

 mm. ; a-c, 0035 mm. ; form of cyst, globular ; diameter of cyst, 

 0290 mm.; habitat, Cypris cinerea; locality, Gorstly Wood, 

 Bishopsbourne, Kent. 



Krabbe tells us in his work " Bidrag til Kundskab om 

 Fuglenes Baendelorme," No. XLV., page 43, that an example 

 of Taenia liophallus, n. sp., is in Leuckart's collection ; that 

 this specimen is 12 mm. long and 8 mm. wide; that it pos- 

 sesses 10 hooks, whose individual length measured 0'035- 

 0038 mm. I must state that I have never in my investiga- 

 tions had the good fortune to find this tape-worm in the 

 viscera of those ducks I have examined. This Taenia was 

 discovered by Leuckart as being parasitic in Cygnus atratus, 

 but Krabbe gives no date of the discovery. 



At the time Krabbe wrote his work but little was known of 

 the existence of the intermediate stage of the Cestodes applic- 

 able to birds ; yet so accurately are the particular points in con- 

 nection with these lowly organisms figured, more especially 

 the hooks, that there need be no doubt in the mind of anyoue 

 in accurately diagnosing any specimen of any species from his 

 drawings of these lowly and aberrant creatures. 



In many cases, and this was the cause of Dujardin forming 

 his genus " Proglottidina," but fragmentary portions of a 

 Strobila are found in the viscera of the host, and then the case 

 becomes more difficult and requires greater care in its elucida- 

 tion ; still, even under such circumstances the distinctive 

 marks of the proglottides and the conformation of the genital 

 organs enable one to arrive at an accurate decision of the 

 nomenclature of the portion of Strobila under our observation. 

 On the other hand but very little doubt need arise in the mind 

 when the seolex with its appendages has been successfully 



