104 BULLETIN 3G, UNITED STATES NATIONAL MUSEUM. 



LAGENOKHYNCriUS 013SCU1UIS (Giay). 



Delplmms obscnrus, Gray, Spic. Zool., 1828, p. 2; ZooL Ere. & Terr., 184(;, p. 37, 



pi. It) ; CMtiilogue of Cetacea, 1st ed., 1850, p. 1U7. 

 Titrsio ohscurus, Gray, Catalogue, 2(1 ed., 18G6, pp. 2G4 and 400. 

 Chjmcnia ohscura, Gray, Proc. Zool. Soc, London, IBGfi, p. 21."); ditto, ISuS, ]>. 147, 



ii<^. 1 (pterygoid bones) ; synojjsis, 18C8, p. G, pi. IG ; snpidemout, 1871, p. 71, (ig. 



3 (pterygoid hones) ; Flower, Proc. Zool. Soc, London, 1883, p. .')12. 

 f Phocwna unsiraUs, Peale, U. S. Explor. Exped., 1st ed,, 1848, p. 33, pi. G, fig. 2. 



Tlii.s species was originally described by Gray from a stuffed skin, but 

 he afterwards included in the species a number of skulls in the British 

 Museum. Tliat the latter were properly referred to the species appears 

 to have been confirmed by Professor Flower upon removing tlie skull 

 from the type-skin in JSSi. (See his List, p. 28.) 



It has been customary among authors since 18G8 to refer this spe- 

 cies to Chjmcnia {=Proflelphi}ins). In the Catalofjnc, however, Gray, 

 although referring the species to Tursio, makes the remark that "the 

 skull of this species is intermediate between the Lcujenorhynclius and 

 J)f/7;/(/>r?f.s'" (Catalogue Seals and Whales, p. 205). After going over 

 the data many times it seems to me that it should ]>roper]y be referred 

 to tlie former genus. There is nothing in the characters of the skull 

 that would militate against this viow, and certain considerations re- 

 garding the exterior seem to confirm it. 



First, the form of the head in the type specimen is unlike that of 

 any species of Frocldphinns of which the exterior is known. There is 

 no real beak, but on the contrary the head slopes gradually from the 

 blowhole to the extremity, as iu Lagenorhynclius acutus. 



Again, the color seems rather that of a Lar/enorhj/nchus than of a Pro- 

 fleJphimfH. Gray's original description contains the following data re- 

 garding the color of the body: 



Collo ventreque albidis, fascea nigra ab angnlo oris nsque ad prinias pectorales; 

 strigaobliqna laterali, alba jiostica; Civternni totns uiger. 



In a young specimen iu-tbe same collection the colors are more defined; but even 

 iu tho older specimens the lateral streaks are to l)e seen in certain positions — a fact 

 -which is not shown in tho drawing. (Spic. Zool., p. 2.) 



The figure of the young individual is not unlike Waterhouse's figure 

 of L. Fitzroyi (Zool. Beagle, pi. 10), which species, indeed. Gray made 

 synonymous with ohscura. Though somewhat generalized, the figure^ 

 in question, as also that of the older individual on the same plate of the 

 Spicitegia (PI. ii, fig. 3), is certainly unlike any ProdelpMnus we know. 



The dimensions of the adult type-skin are as follows (measured in 

 straight lines) : Total length, G5 inches ; tip of snout to corner of 

 mouth, 8.7 inches; to eye, 10 inches; to blowhole, 9.5 inches: to ante- 

 rior base of pectoral fin, 1G.5 inches ; to anterior base of dorsal fin (fol- 

 lowing the curves), 31.75 inches; length of the dorsal fin, inches; 

 vertical height of dorsal fin, 7.5 inches ; length of pectoral fin, 11 inches; 

 greatest breadth of pectoral fin, 3.5 inches; breadth of caudal fins, 

 15.75 inches. 



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