1885.] PROCEEDINGS OF UNlTfit) STATES NATIONAL MUSEUM. 95 



iO.OO (average of eleven specimens, 9.19) ; tail, 6.20-7.10 (average, 6.G2) ; 

 culmen, .70-.82 (average, .75); tarsus, 2.35-2.65 (average, 2.54); middle 

 toe, 1.15-1.30 (average, 1.24). 



The specimens of this new form (including eight examples in alcohol) 

 were collected by the naturalists of the United States Fish Commission 

 steamer Albatross, Capt. Z. L. Tanner, commander. 



ON A NEW SPECIES OF PORPOISE, PHOCiENA DALLI, PROM 



ALASKA. 



By FREDERICK ^V. TRUE. 



Curator of the Department of MamviaU. 



The species of Phoccena hitherto described are seven in number. 

 These are — 



Phoccena communis, Lesson. Phocana spinipinniSj Burmeister. 



Phoccena vomerina, Gill. Phoccena tuherculifera, Gray. 



Phoccena hrachyclon, Cope. Phoccena pectoralis, Peale. 



Phoccena Uncata, Cope. 



The P. pectoralis of Peale, as I shall endeavor to prove in another 

 communication, is in reality a Lagenorhynchus, and probably synonymous 

 with L. electra, Gray. P. tuherciilifera of Gray was finally admitted 

 by that author to be only a variation of P. communis. The opinion has 

 lately been expressed by Professor Flower that the last named species is 

 probably cosmopolitan, and that P. brachycion and P. vomerina are synony- 

 mous with it.* If this view is correct, and I am inclined to believe that 

 it may be, the known species of Phoca'na will be reduced to three, namely, 

 P. communis, Uneata, and spinipinnis. To this list I am enabled to add 

 a new species, through the kindness of Mr. William H. Dall, who has 

 placed at my disposal his notes upon and drawings of two specimens 

 of a peculiar porjioise belonging to the genus, captured ofl* the coast of 

 Alaska in 1873. The skeleton of one of these specimens was sent to 

 the Army Medical museum in this city, where it was unfortunately de- 

 stroyed by rats. The skull, however, was preserved and is now in the 

 possession of the l^ational Museum. The second specimen, which I 

 shall now describe, was one of a school of five or six met with in the 

 strait west of Adakh Island, one of the Aleutian group, August 13, 1873. 

 It proved to be a male. 



Phocana Dalli, sp. nov^ (Plates II-V.) 



Length 6 feet. General color black. A cordate area of white occu- 

 pies the bellj^ and lower half of the sides, from a point in line with 

 anterior margin of the dorsal fin to one considerably behind the vent. 

 This area is faintly streaked with very fine dark lines, especially nu- 



*P. Z. S., Loudou, 1883, p. 505. 



