SPECIES OF ECHINORHYNCHUS PARASIT1C IN THE CETACEA 



265 



figures this région is exposed, in ail theother ligures in this article 

 except Ihe enlarged head of Parona's spécimen, this région is invi- 

 sible owing to the retraction of the proboscis. Behind the retina- 

 culum, which is covered with scales, there is no neck, but the pré- 

 sence of such a constriction is variable, the 

 neck certainly varies in four spécimens of the (jv^. 

 saine species in my possession, and is probably 

 determined by the amount of growth of the 

 free edge of the cavity in the walls of the intes- 

 tine of the host in which the proboscis and the 

 relinaculum are imbedded. 



Perhaps the most important point in which 

 Leuckart's spécimens resemble the earlier 

 described species is that the caudal end of the 

 maie is terminated by a rounded bursa, the 

 présence of this confirmed by other resem- 

 blances strengthens the belief that E. pellucidus 

 is a synonym of E. turbinella. 



I was at one time rather inclined to agrée 

 with the suggestion of Borgstrôm that E. capi- 

 tatus Diesing may be identical with E. porri- 

 gens Rudolphi. The E. capitatus Dies. which 

 Corrado Parona (1) described from the intestine 

 of a Globicephalus mêlas (Traill) the Pilot, Ca'ing 

 or Round headed Whale, is almost certainly the 

 same species as Diesing's, but hère there is a 

 certain difïiculty because as far as I can see 

 nowhere in the text or in the legend of the 

 plate is the size of the parasite mentioned, ail 

 we are told is that the dimensions of E. pellu- 

 cidus, E. brevicollis and E. turbinella are much 

 smaller than those of the species in question. 

 Von Linstow's spécimens measured 100 cm in 

 the female and 53 cm in the maie. In the drawing 

 given by von Linstow (2) the whole of the 

 retinaculum is covered by scales, but in Parona's figure the ante- 



Fig. 4. 



Echinorhyn- 

 chus pellucidus F. S. 

 Leuckart. — A, maie; 

 B, female. X 9. 



(1) holl. Mus. Genova, n° 15, 1893, p. 1. 



(2) Archiv fur Naturg., Jahrgang 46, I, 1880, p. 49. 



Archives de Parasitologie, II, n° 2, 1899. 



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