8tj BULLETIN 36, UNITED STATES NATIONAL MUSEUM. 



The original description is far from satisfactory, and, indeed, apjilii's 

 equally well to several other species of tbe genus. Since, however, Gr;iy 

 expanded his description iu later publications so that it is plain to what 

 species he referred, it seems best on the whole to retain the name which 

 has secured a footing iu the literature rather than to displace it by 

 Schlegel's D. eschrichtii, published many years later. 



I am unable to enter into the question of the identity of Schlegel's 

 D. eschrichtii and Rasch's I>. leucopleurus^ since I saw the type-skeleton 

 of neither. Professor Flower does not state that he saw the type of the 

 former himself, but simply that it "is still to be seeu in the Leyden 

 Museum." He is convinced, however, of the identity of the two 

 species. If such be the truth (I do not presume to appeal from Pro- 

 fessor Flower's decision), the statement of the number of vertebra? in 

 Schlegel's description must be incorrect. The formula derived from 

 his description would be as follows: 0. 7; D. 15; L. 32; Ca. 37 =01. 

 This number corresponds more closely with that found in L. aJbirostris 

 than with that found iu L. Icucoplcnrus. I shall use Gray's name, L. 

 acuUis, throughout this section as synonymous with L. ieucopJeurus and 

 L. eschrichtii. 



The Lagenorhynchus perspicillattis and Lagenorhynchus guhernator of 

 Professor Cope I regard identical with L. aciitns. L. guhenudor^ how- 

 ever, is founded ou a. young individual (as I have determined from an 

 examination of the typecast and a photograi)h of the individual from 

 which the same was made), and may, therefore, be disiegarded. The 

 typecast of L. i)erspiciUatus agrees absolutely- in color with Rasch's 

 figure of X. leucopleurus, and the measurements also agree. The meas 

 urements of L. perspiciUatns also agiee very closely with those given 

 by Duguid for L. acutiis. Moreover, the measurements of the large 

 series of skulls mentioned by Professor Cope, which is still in the 

 Museum, agree with those of the type of L. leucopleurus^ as will be 

 seen by reference to the table on p. 87. I have also carefully comj^ared 

 one of the skeletons from Cape Cod, referred to by Professor Cope, with 

 a skeleton of L. acntus from the Fariie Islands, which was lent me for 

 study by Dr. J. S. Billings, Director of the U. S. Army Medical Museum, 

 and can find absolutely no difterences but such as are referable to iudi- 

 vidual variation. The figure accompanying Professor Cope's paper 

 (Proc. Acad. Nat. Sci. Phila., 1876, pi. iv), though styled Lagenorhyn- 

 chus perspiciUatns, is really that of one of the casts of the young L. 

 guhernator. It agrees exactly with the photogra])h in the Department 

 of Mammals, and may be regarded as an excellent figure of a young 

 L. acuius. The name L. bombifrons^ alluded to by Professor Cope (1. c, 

 \). 138), is a slip of the pen, L. jicrspiciUatus being intended. 



The distinctions between tnis species and the remaining members of 

 the genus will be pointed out iu treating of the latter. 



