BEAKED WHALES, FAMILY ZIPHIICffi TRUE. 



65 



Gervais " of the skull on which it was based that the latter presents the combination 

 of characters peculiar to the female of Z. cavirostris. This skull, which was from 

 Aresquiers (Herault), France, was 888 mm. long, and hence, presumably, adult. 

 The mesirostral ossification is but slightly developed, the prenarial concavity mod- 

 erate, the teeth small, slender, and cylindrical, with closed roots and a diameter of 

 14 mm. There seems to be no sufficient reason for regarding this skull as repre- 

 senting a species distinct from cavirostris. 



The specimen from Buenos Ayres described and figured by Burmeister in 1868 * 

 was an immature male. In the skull the mesirostral ossification was lacking, the 

 premaxillse were flat, and the teeth conical and acuminate, with open roots, and a 

 diameter of 12 mm. This individual was 12 feet llj inches (3.95 m.) long, and 

 hence about as long as the Charleston specimen, but the skull was apparently 680 

 mm. long, while that of the Charleston specimen .is 797 mm. long. In the latter 

 the teeth are 45 mm. long and 10 mm. in diameter, while the tooth figured by Bur- 

 meister is 31 mm. long and 12 mm. in diameter. From these data it appears 

 improbable that the sex of immature individuals can be determined from the skull 

 or teeth. 



TEETH. 



The teeth of the various North Atlantic and North Pacific specimens merit 

 a somewhat more detailed description than is given on pages 50 to 53. Six pairs of 

 teeth from six different individuals are available for comparison. Their dimensions 

 are as follows: 



Dimensions of the teeth of Ziphius cavirostris. 



Cat. 

 No. 



21975 

 20971 

 22069 

 20993 

 21248 

 49599 



Locality. 



Charleston, South Carolinao 

 Barnegat Cit.v, New Jersey. 



Bering Island 



....doi> 



....do 



Newport, Rhode Island 



a Type of Z. semijunctus. 



6 Type of Z. grebnitzfcii. 



21975. Charleston, South Carolina. — Young female. (Type of Z. semijunctus.) 

 The teeth are slender, conical, and acuminate, largest at the base and tipped for 

 about 2 mm. with white enamel. The remainder of the teeth is coated with a thin 

 layer of cement. The teeth in what appears to be their natural position protrude 

 horizontally from the mandible for about 17 mm. They are slightly curved upward 

 near the tip and are oval, or elliptical, in section, the transverse diameter being 

 a Uttle less than the vertical diameter. They are a little flattened externally. 



aZooI. et Pal^ontol. fran?., 2d ed., 1859, p. 287, pi. 39, figs. 2-7. 

 b Anal. Mu8. Pub. Buenos Aires, vol. 1, 1868, pp. 301-366, pis. 15-20. 



