G2 



BULLETIN 36, UNITED STATES NATIONAL MUSEUM. 



Prodelphinus doris (Gray). 



plagiodon (Cope), 

 uorrualis (Gray). 

 breviiuauus (Wagner). 

 frtBuatus (F. Cuvier). 

 frontalis (Dnssninier). 

 atfcenuatns (Gray), 

 capcnsis (Gray). 



Prodelphinus punctatus (Gray). 



raalayanns (Sclilegel). 

 pseudodolpUis (Wagnwr). 

 longirostris (Gray), 

 steuorbynchus (Gray), 

 microps (Gray), 

 alope (Gray). 



Several other species were assigned to this genus by Professor 

 Flower which seem to me to belong elsewhere. Of these G. ohscura 

 Gray, G. shnilis Gray, and Electra thicolea Gray, seem to me to belong 

 to Lagenorhyiichus ; Delphiiius roselveiifris, Hombron and Pacheran, I 

 prefer to leave in the genus to which it was originally assigned; D. 

 .superciliosa, Lesson and Garnot, is not sufficiently well defined to admit 

 of an opinion. 



PRODELPHINUS CCERULEO-ALBUS (Meyen). 



DelphitiKS cocndeo-albus, Meyon, Nova Acta Nat. Curios., xvi, pt. 2, 1833, pp. 609, 

 610, pi. 43, lig. 2; Wagner, Sclireber's Saugetb., 7tb Th., 1846, p. 336, pi. 363; 

 Gray, Zool. Erebus aud Terror, 1846, p. 42. 



Lageiiorhynchus ca:ruleo-albiis, Gray, Catalogue of Cetacea, 1st ed., 1850, pp. 100, 

 101; 2d ed., 1866, [.p. 268, 269. 



This species is based on a s])ecimeu obtained by Meyen on the east 

 coast of South America, in the vicinity of the Rio de la Plata, and de- 

 l)osited in the Zoological Museum of Berlin. 



The skull, which 1 was enabled to examine in 1887 through the kind- 

 ness of Dr. migendorf, resembles that of P. euphrosyue, and also in 

 some respects that of P. doris. It is peculiar in having very small oval 

 temporal fossje, which ore directed upwards strongly behind. The 

 intermaxilhv are much arched in the middle of the rostrum, and tlje 

 pterygoids are strongly carinate. In the skeleton I counted 7 cervical 

 vertebrae, 14 dorsal vertebric, and 52 lunibars and caudals, but a few 

 more should probably be added to the number of the latter. The trans- 

 verse processes of the lumbar vertebme are slender and are directed 

 forwards. 



The color ot the species, as indicated in Meyen's figure ami descrip- 

 tion, is apparently quite different from that of any other known species. 

 (See Synojjsis, ji. 1G3.) 



Why this species was included by Gray in the genus LcKjenorhynchus 

 is not clear, since the form of the skull and beak are characteristic of 

 Prodelphinus. Cassin's reasons for associating with this si)ecies the 

 Delphinus albirostrafus of Peale are equally unsatisfactory.* I have 

 been unable to identify the latter species. 



*Cassin, U. S. Explor. Exped., Mauiiualogy aud Ornithology, 2d ed., 1858, p. 31: 

 Atlas, pi. 6, fig. 2. 



