﻿2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 59 



They constitute, indeed, the only comprehensive series of good illus- 

 trations of fossil whalebone whales thus far published. 



Brandt's work, unlike the foregoing, is in large measure critical 

 and exact, but is, nevertheless, somewhat unsatisfactory on account 

 of its discursiveness, its numerous supplements, and its more or less 

 involved and indefinite system of classification. It suffers also from 

 its very badly drawn plates, which, in many instances, are entirely 

 useless for critical comparisons. 



On account of the obscurity in which the subject was involved, I 

 finally determined to disregard the literature, and to endeavor to form 

 diagnoses directly from the illustrations furnished by American and 

 European authors, including those already mentioned, together with 

 such specimens as were available for study. The resulting diagnoses 

 based on characters of the skull, which are given below, were com- 

 pleted May i, 1909. A few months afterwards I received a copy of 

 Dr. Winge's paper on Plesiocetus and Squalodon from Denmark, 1 

 which contains very valuable critical remarks on the fossil genera 

 under consideration, though no attempt is made to formulate diag- 

 noses of them. His opinions are, however, in close accord with my 

 own, and as the article is written in Danish, it has seemed to me 

 desirable to present a translation of his remarks in this place, in so 

 far as they relate to the American forms. (See p. 5.) 



A summary of his conclusions is as follows : 



Valid genera of fossil whalebone whales, according to 



WlNGE 2 



Aulocetus Cetotherium Megaptera 



Balcenoptera Herpetocetus Plesiocetus 



Genera of doubtful validity, according to Winge 



Cetotheriomorphus Pachycetus Tretulias 



Mesoteras Rhegnopsis Ulias 



Metopocetus Siphonocetus 



The complete list of genera considered by Winge, with his opinion 

 and my own regarding each, is as follows : 



1 Winge, H. — Om Plesiocetus og Sqvalodon fra Danmark. Vidensk. Meddel. 



fra den naturhist. Foren. i Kjjzfoenhavn for 1909, pp. 1-38, pis. 1, 2. 

 1910. 

 Separately published, April 20, 1909. 



2 The genera of Right whales and the genus Rhachianectes are not included. 



