PIIOCENA COMMUNIS. 121 



iiLso vary j^reatly in proportions, we sluiU gain nothing by compari>sou. 

 0:i this point we innst await the result of future investigations 



We turn linally to the question of color. The color of i*. Uiieafa is 

 accurately described by Professor Cope (1. c). The back upper half of 

 the head, posterior part of the tail, flukes, and pectoral fins are black. 

 The sides are pinkish and the belly is white. A black line passes from 

 the base of the pectoral fin to the corner of the mouth. The edges of 

 tlie lower lip are black. The Cape May female and another female 

 si)ecimen, 5 feet 1 inch long, have nearly the same coloration, except 

 that the sides are yellowish instead of pink and the light color of the 

 belly extends nearly to the flukes and leaves only a slight band of dark 

 color around the lower lip. The Cape May specimen also has no dark 

 band fiom the pectoral fin to the mouth, but it exists in the second 

 female. Are these differences in color sufficient to warrant the repara- 

 tion of P. Uneata ? 



M Fischer's figure of an old female (PI. Vii, fig. 1) agrees in colora- 

 tion and form with the cast of P. Uneata, except that the sides are gray 

 instead of pink and that the band of color from the pectoral fin to the 

 mouth is broad and gray instead of narrow and black. 



In point of color, Scammon's description of P. vomerina is applicable 

 to M. Fischer's specimens of P. communis. I subjoin Scammon's descriii- 

 tion of the female of P. vomerina and the description by Lafont of a 

 female of P. communis : 



r. communis (female). 



Dos noir j flancs d'aii gi'is do fer jiispd 

 de blaiic; abdomen d'uu Llanc uu pea 

 gi'isatre; pectorals noires; iinelignenoire, 

 ties otroite, part de lenr attaclio et se 

 dirige vers la commissure labiale ; rostre 

 noir. (Lafout.) [Fischer, 1. c, p. 165.] 



P. vomerina (female). 



The female is of the same color above 

 (black) ; it is lighter ou the sides, with a 

 narrow black streak rniiuiug from the 

 comer of the mouth to the pectorals, and 

 the lower portion of the animal is of a 

 )nilky wbiteiiess ; yet the jjectoral and 

 caudal fins are black underneath or of a 

 dark gray. [Scanimou, Marine Mam., 

 p. 95.] 



It will be observed that Lafont's specimen only differs in having the 

 wliite of the belly ''un pen grisatre." In another specimen this region 

 was white, as in Scammon's P. vomerina. 



Summiiig u;) the available evidence I find no reason to regard P. 

 hracliijcion or P. vomerina. as distinct from P. communis. P. Uneata, if 

 distinct, differs only in color, a character which in this genus must be 

 looked upon with distrust. 



