24 BULLETIN oG, UNITED STATES NATIONAL MUSEUM. 



outward, and as the symphysis is not keeled the terminal portion of the 

 mandible has the least depth, which is not the case in Tursio2)s. In the 

 last-named genns tlie beak is depressed, while in Stcno it is compressed. 

 The teeth are equally numerous in the two genera, but in Stow the 

 crown is rugose. As regards the vertebrae, the number in four regions 

 of the body is practically alike in both genera, but, according to the 

 measurements given by Dr. Peters for S. pcrsplcUlatus, the combined 

 length of cervical vertebrii3 would appear to be considerably greater in 

 ISteuo than in Tursiops. 



From Sotalia the present genus is distinguished by its conjoined 

 pterygoids and its less numerous and rugose teeth. 



STENO EOSTRATUS (Desmarest). 



Vdphinus rostralus, Ciivier, Desmarest, Nouv. Diet. d'Hist. nat., ix, 1817, p. IGO; 



Maumialogie, 1822, p. 515. 

 Dclphinns rostratiis, Shaw (!), Cuvicr, Anu. ilu Mus6um, xix, 1812, p. 10. 

 DcJphinm frontalus (pars), Cuvier,'Oss. loss., 2d. ed., v, 1823, j). 278. ( Fjrfc Flower.) 

 DeJphinus rostiatns, G. Ciivier, Eoj^ue Auiuial, 2 ed., i, 1829, p. 289; F. Cuv., iu 



Oss. foss., 4tb ed., 1836, p. SiJ, 121; Hist. uat. des C6tac^s, 1836, p. 156. 

 Dclphinns hredanensif, Cuv., Lessou, Hist. Nat. des Maiumif. et Oiseaux dccouvert 



depius 1788, 1828, p. 206; Van Breda, Nicuwe Vcrbandl. Nederl. lust., ii, 



1829, pp. 235-237, pis. 1, 2. 

 DelpMnorhijnclnishredanensis, Lessou, Hist. Nat. des Mamuiif. ctOiscaux dccouvert 



dcpnis 1783, 1828, p. 441 (table m6tbod.). 

 Stcno rosiratus aud S. frontalus, Gray, Zool. Erebus aud Terror, 1846, p. 43. 

 Stcno fronfafns, Gray, Synop. Whales aud Dolpbins, 1868, p. 5. 

 GJyphidcJphis rostratns, Gervais, Zool. aud Faleou. Fraug., 1859, p. 301 ; Ost6og_ 



des Cetacds, 1880, p. 594, pi. xxxvii, iigs. 8-11. 

 Dclphinns planiccps, Scblegel, Abbaudl. aus d. Geb. Zoologie, bcft I, 1841, p. 27 



{not Vau Breda). 

 Stcno comprcssus, Gray, Zool. Erebus aud Terror, 1846, p. 43, pi. 27. 

 Dclphinns Ilcinwcirdtii, Scblegel, Abbaudl. Geb. Zool., heft i, 1841, p. 27, pi. 3, fjgs. 



2,3. 

 DelpUnus rvrncttyi, Desmarest, Mammalogie, 1822, p. 513. 



The peculiar synonymy of this species has received thorough treat- 

 ment at the hands of Professor Flower (Cliarac. and Div., p. 482 et seq.), 

 to whose account I can add but little. He has, however, fallen into 

 the same error as Schlegel in accrediting the name I), planiccps to Van 

 Breda. The latter writer used the name of 1). hredanensis for the 

 species, which name, according to his own account, he took from Lrs 

 son's Histolrc naturelle des Mammiferes decourert depiiis 1788. 



Desmarest credits the name 7>. rostratus to U. Cuvier, but incorrectly 

 it appears, for Cuvier simply states that his specimens belong possibly 

 to Shaw's BeJphinus rostratus. It api)ears to nie, therefore, that Des- 

 marest's name should be appended to the name of the species instead of 

 Cuvier's. 



Van Breda appears to have published his account of the species, 

 under the name of I), byedancnsis, before Cuvier had recognized that 



