THE URINO-GENITAL SYSTEM OF THE 

 FIN WHALE (BALAENOPTERA PHYSALUS) 



By F. D. Ommanney, A.R.C.S., b.Sc.(lond.) 

 (Plates II, III; text-figs. 1-39) 



INTRODUCTION 



The urino-genital system of the Cetacea has been frequently described. Hunter (1787) 

 and Rapp (1837) were among the earliest authors to give an account of it. Since 

 these authors wrote, Yves Delage (1885), who described the gross anatomy of a stranded 

 specimen of an adult Balaenoptera musculus (now B.physahis), Turner (1870), Beauregard 

 and Boulart (1882) and Daudt ( 1 898) have given the best accounts of the system. Struthers 

 (1893) described the muscles in the genital region in a paper which has formed the basis 

 of all subsequent accounts. Meek (19 18) and Anthony (1922) also made contributions 

 to this subject, the former dealing with the genital system of Phocaena communis 

 (now P. phocaena) and the latter that of Mesoplodon bidens. Anthony's paper treats the 

 subject comparatively but describes only the male sex. 



With the exception of Anthony's paper, however, there is a scarcity of clear figures in 

 the literature of this subject, so that a still further contribution will not be out of place if 

 it does no more than make good this deficiency. In some of the earlier descriptions the 

 material used had evidently been long preserved in formalin and seems to have under- 

 gone distortion. This is especially noticeable in Daudt's paper. 



During the course of the work the author was particularly struck by certain primitive 

 and distinctive features in the urino-genital system of the Fin whale. An attempt has 

 been made in what follows to emphasize these points and to consider them compara- 

 tively with relation to the conditions found in other orders and sub-orders of Mammalia, 

 with a view to making deductions, if possible, concerning the relationship of the 

 Cetacea to other mammals. 



The material upon which this work was carried out consisted of four fin whale 

 foetuses — two males 2-65 and 1-23 m. in length and two females 2-1 and 173 m. in 

 length. Dissections of these were made at the Marine Biological Station at South 

 Georgia during the southern summer of 1930-1. A great many kidneys were extracted 

 during work on the flensing platform. These were measured and examined in the 

 laboratory and form the basis of the account of the kidney and the tabulated measure- 

 ments at the end of this paper. 



The author wishes to thank Sir Sidney Harmer, K.B.E., F.R.S.,and Dr J. F. G. 

 Wheeler, late of the Discovery Investigations, for valuable help and advice and also 

 Mr E. R. Gunther, of the Discovery Investigations, for useful criticism. 



