436 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxiir. 



We have already shown that Nogagus validus and Pandarus Irrevi- 

 caudis are probably the male and female of the same species, and 

 hence the fact that the present species was found with them would 

 not be specially si2;nificant. 



Claus in 1875 mentions a similar form found in the Mediterranean, 

 and concludes that Dana's Specilligus is really a Nogaus male of 

 some genus belonging to the Pandarinse. He only mentions the 

 genera Dinemaiura, EcJithrogaleus , and Pandarus, but if we interpret 

 his meaning aright these are given rather as samples than as com- 

 prising the onl}^ genera to which Specilligus could belong. 



Gerstaecker in Brohn's Thierreich considered that this genus of 

 Dana's was very closely related to if not indentical with Nogaus. 

 Thomson mentions the species in his Parasitic Copepoda of New Zea- 

 land (1889), but adds nothing new in the way of description or 

 identification. 



Bassett-Smith in 1899 makes " Nogagus curticaudatus'" a synonym 

 of Gangliopus injriforinis, referring to Steenstrup and Liitken for his 

 authority. But he made a bad mistake both in his spelling of the 

 specific name and in his reading of the Danish paper referred to. 

 Steenstrup and Liitken declare that Gerstaecker' s Nogagus angustulus, 

 and not the present species, was taken on the same fish with Pandarus 

 dentatus Edwards and Gangliopus pyriformis Gerstaecker. The state- 

 ment they make in reference to Dana's species has already been given. 



It is therefore practically certain that the present species is a 

 Nogaus form, that it does not belong to any of the genera just men- 

 tioned, and that it does conform in all its details with the male of the 

 genus Nesippus. Dana's description, though brief, is ver}^ accurate 

 and his figures are excellent, but as the Museum collection contains 

 several fine specimens of the species a more complete description has 

 been given to accompany this definite location in the genus Nesippus. 

 There are two lots of specimens, one, Cat. No. 6917, U.S.N.M., taken 

 from a Carcharias between Papua and Japan on the Challenger Expe- 

 dition, and obtained through exchange with G. S. Brady, of England; 

 the other. Cat. No. 32742, U.S.N.M., contains five males taken from a 

 10-foot shark at Station 2422 by the Fisheries steamer Albatross in 

 1885. With reference to the conspicilla they show plainly in some 

 specimens, while in others from the same bottle they can be seen only 

 under strong light, transmitted through the body of the specimen. 

 They evidently belong to the internal anatomy and bid fair, on further 

 examination, to be closely related to the frontal attachment gland. 



