24 BULLETIN 3G, UNITED STATES NATIONAL MUSEUM. 



outward, aiul as the symphysis is not keeled the termiual portion of the 

 mandible has the least depth, which is not the case in Tursiops. In the 

 last-named genus the beak is depressed, while in Steno it is compressed. 

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

 crown is rugose. As regards the vertebra^ the number in four regions 

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

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

 length of cervical vertebra would appear to be considerably greater in 

 Stciio than in Tursiops. 



From Sotalia the present genus is distinguished b}^ its conjoined 

 pterygoids and its less numerous and rugose teeth. 



STENO EOSTEATUS (Desmarest). 



Delphinus rostralus, Cnvier, Desmarest, Nouv. Diet. d'Hist. nat., ix, 1817, p. IGO; 



Mauinialogie, 1822, p. 515. 

 Delphinus rosiratus, Shaw (?), Cuvier, Anu. du Mus6iim, xix, 1812, p. 10. 

 Delpliinns fi-ontatns (pars), Cuvier, Oss. foss., 2cl ecL, v, 1823, ji. 278. ( Firfe Flower.) 

 Delphinus rostratus, G. Cuvier, E^gue Animal, 2 ed., i, 182i), p. 289; Y. Cuv., iu 



Oss. foss., 4th ed., 1836, p. 86, 121; Hist. uat. des C«Stac<Ss, 1836, p. 156. 

 Delphinus hredanensif, Cuv., Lessou, Hist. Nat. des Mammif. et Oiseaux ddcouvert 



depius 1788, 1828, p. 206; Van Breda, Nicuwe Verhandl. Nedcrl. lust., ii, 



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

 Delphinorhynchushredanensis, Lessou, Hist. Nat. des Mammif. ctOiscauxddcouvcrt 



depuis 1788, 1828, p. 441 (tabic mdthod.). 

 Stcno rosiratus and S. frontahis, Gray, Zool. Erebus and Terror, 1846, p. 43. 

 Steno frontatns, Gray, Synop. Whales and Dolphins, 18G8, p. 5. 

 Glypliidclphis rostratus, Gervais, Zool. and Paleon. Fraug., 1851), p. 301 ; Ost<5og_ 



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

 Delphinus planiceps, Sclilegel, Abhandl. aus d. Geb. Zoologie, heft i, 1841, p. 27 



{not Van Breda). 

 Steno comprcssus, Gray, Zool. Erebus and Terror, 1846, p. 43, j)!. 27. 

 Delphinus Eeinwardtii, Schlegel, Abhandl. Geb. Zool., heft i, 1841, p. 27, pi. 3, figs. 



2,3. 

 Delphinus Pernettyi, Desmarest, Mammalogie, 1822, p. 513. 



The peculiar synonymy of this species has received thorough treat- 

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

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

 the same error as Schlegel iu accrediting the name B. planiceps to Van 

 Breda. The latter writer used the name of D. brcdanensis for the 

 species, which name, according to his owii account, he took from Lcs 

 son's Ilistoire naturelle des Mammiferes decouvcrt depuis 1788. 



Desmarest credits the name I), rostratus to G. Cuvier, but incorrectly 

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

 to Hhnvf^s Delphinus rostratus. It appears to me, 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), brcdanensis, before Cuvier had recognized that 



