PIIOCyENA COMMUNIS. llll 



I lie proximal ends of the premaxilhi;, tbe uasals, and the portion of the 

 vomer visible on the palatine snrface, — I find that no two of tbe East- 

 l)ort skulls agree. Tliey can therefore scarcely be regarded as of im- 

 portance in distinguishing the species. 



In the List of the Cetacea in the British Miisenm,* Professor Flower 

 intimates that the skull of P. I'omer/Hrt is larger than any other Pho- 

 ciuna skull in that collection. In looking over our own series, I was 

 at first struck by the size of two of the skulls of P. vomerinaj but ou 

 comparing M. Fischer's measurements I find that neither of these is 

 as large as that of his specimen " D. Femelle tres adulte,^''] nor are they 

 as large as Malm's specimen "t."| The largest skull of P. vomcrina, 

 No. 9078, from Puget Sound, is 29.3"" long, but it does not show any 

 considerable occipital crest nor other signs of age; while, on the other 

 hand, No. 1C610, an adult female of P. hrachijcium from Cape May, 

 N. J., though only 26.G"" long, has the crest strongly developed. That 

 this fact is without significance, however, appears from the considera- 

 tion of two other skulls, both of which are 26.6''"' long. One of them. 

 No. 9164, is from Eastport, Me., and should represent P. hrachycium ; 

 tlie other. No. 9077, is from Puget Sound, and represents P. vomcriaa. 

 The latter has the sutures between the elements of the occipital closed, 

 while in the former they are still open. The crest also is rather more 

 ]»ronounced in P. vomerina. We have here, therefore, a fact exactly 

 opposed to that just presented, namely, in two skulls of equal size that 

 of P. vomerina appears to be the older, and might be presumed, there- 

 fore, to be the smaller species. It appears, therefore, that the absolute 

 size of the different skulls gives us no grounds for the distinction of 

 si)ecies. 



As regards proportions, there can be no question that the girth of the 

 body of the specimen which Professor Cope called I\ lincata, as com- 

 ])ared with its length, is much less than in the specimen from Eastport, 

 with which he compared. But it should be held in mind that the latter 

 is only 43i inches long, while the type of P. llneaia is 70 inches long. 

 The former is evidently very young, since a skeleton (No. 13301, from 

 Eastport), which measures fully 46 inches, has the sutures defining the 

 limits of the elements of the occipital still open. 



The large size of the hea 1 and the thickness of the body I look upon 

 as fietal characteristics not yet outgrown. 



It is manifestly unwise to compare the type of P. lineata, which shows 

 evidence of being adult, with so young an individual as the Eastport 

 specimen. Fortunately we have two other casts nearly equaling the type 

 of P. lineata in length. Of the larger of these, No If^f^, an adult female, 

 we have the entire skeleton. In the following table are compared the 



*List of the Cetacea in the Brit. Mas., 1835, p. 16. 



tFisclier, Actes Liun. Soc. Bordeaux, xxxv, 1S81, p. IfiS. 



tK. Svenska Veteiis. Akad. Haudliug., new ser., ix, i, 1871, p. 75. 



