SI'ECIES OK ECHhNUHIIYNcnUS PARASITIC EN THE CETACEA 2117 



in wliich il dillVrs markedly from the other Eohinoi'hyiiuhi livmg 

 in Cetacea, and to my mintl a feature of spécifie value, is that l lie 

 retinaculum bears no spines or hooks orscales, is in tact, unarmed. 

 Tliis aparl trom size, outline and colour very definitely séparâtes 

 this species Irom any other thaï lias hitherlo been recorded from 

 the Whales. 



Immediately b.ehind llie retinaculum the neck is very harrow, 

 only l rai " in breadth, and it swells but very gradually as it passes 

 haekward until the full width of Ihe hody, some \ or 5 mm is 

 attained; the posterior end does not taper and is bluntly rounded. 



This parasite is described by Rudolphi and by Westrumb (1) 

 Irom the intestine of Balsena rostrata. In von Linslow's invaluable 

 (>ompendium Ihe host is ^iven as BaUena mysticetus Linn. but I do 

 not find in either Gray's British Muséum Catalogue 1866, or in Sir 

 William Flower's List l<S8o, that B. rostrata is a synonyni of B. 

 mysticetus and I a m iuclined to tbink that host was either the Rottle- 

 nose Whale Hyperoodon rostratus Mùll. or more probably the Lesser 

 Rorqual or Pike Whale, Bakmoptera rostrata Fabr. 



The two spécimens sent me by Professor Collett were taken by 

 hiin from the Hunipback \ATiale, Megaptera boops L. The Norwegïan 

 professoi- lias Unis added a new host for tliis species of parasite. 



Nothing is known as to the alternate host in which the larval 

 Echinorhynchuses pass their lives, and with a view of aiding 

 research in this direction 1 bave added to the following synopsis a 

 few notes on the food of the Cetacea for the most part kindly sent 

 me by Professor Collett. 



The Echynorhynchidae which inhabit Cetacea are then as follows : 



1. — EcHLNORHY.\CHUs BREVicoLus Malin. — Fouiid by Malm in the 

 intestines of Bahenoptera Sibbaldi Grey, Ihe largest of ail known 

 animais which passes « the winter in the open seas, and approaches 

 the coast of Norway at the end of x\pril or the beginning of May ». 

 At this time its sole food is Boreophausia inermis. It never eats Fish. 



1. — Echinorhynchus CAi'iTATUS von Linstow. — Von Linstow 

 records this species from Pseudorca crassiden* Owen and Corrado 



(1) Westrumb, De Helminthibus Acanth'ocephalis. Hannover, 1821, p. 29. 



