154 MR. W. H. FLOWER ON THE SKELETON 
inches. 
Greatest breadth at postorbital processes of frontals . . . . 88 
Breadth of anterior narial apertures . . . . .. =. . . 24 
Breadth of rostrum at base . . . ay srokeeuy Senet 
Breadth of rostrum at a quarter of its deusth as bases. 6). 62:9 
Breadth of rostrum atthe middle. . .. . s . 1:85 
Breadth of rostrum at three-quarters of its length eee iat ansclit4, 
Length of uppertooth-lines)i-en hel ApaWs (hey Ft xen CS 
Mandible» ‘enpti et ramus:) .Jeetd> -aheetes ST uke es) 
Tenrth: of symphysis, 92 fF eo nelinien ot #889 
Teneth oftnethaline cysts defies 0s ee Seabees 
iBreadthiaticondyless/< Paeks go) - Noemeyraie! 2S 
Height at ecoroneid processivy i Glin! - Gat ered 
The occipital foramen is subcircular, slightly higher than broad. ‘The tentorium is 
largely ossified. The temporal fosse are bounded by very prominent ridges. The 
postorbital processes of the frontals do not meet the squamosals by a space of 2 inches. 
The anteorbital process is well marked, its depressed outer extremity is formed by the 
jugal. The styliform portion of the jugal is 4 inches long. ‘The median postnarial 
prominence of the frontal is strongly marked, and rises slightly higher than the supra- 
occipital or the nasals; the latter are ankylosed both to the frontals and the ethmoid. 
The narial apertures exhibit the usual want of symmetry, inclining to the left. The 
upper extremity of the left pramaxilla is shorter and much more attenuated than that 
of the right. The rostrum is rather broad at the base, and gradually tapers towards the 
middle; it then becomes much compressed, and retains very nearly the same breadth to 
its termination. Correspondingly the palate is broad and flat behind, but narrow and 
with a deep median groove in its anterior two-thirds; a narrow strip of the vomer 
appears for a space of 2} inches in the hinder part of this groove; as in the allied 
forms, there are no lateral grooves. 
The palate-bones are of larger extent than in most Dolphins; and the form of the 
pterygoids is quite peculiar (see Pl. XVIII. fig. 1, pt): instead of meeting in the 
middle line and concealing the hinder edge of the palatines, they are widely separated 
throughout their whole extent, and gradually recede from each other till their hinder 
apices are 2 inches apart. In the other large Stenos, as in nearly all other Dolphins, 
the pterygoids are in contact in the median line for a distance of 2 inches. In Steno 
lentiginosus, Ow., the inner edges of the pterygoids do not meet, though they are 
parallel for the greater part of their extent. In D. gadamwu, which Owen places in 
this section, and Gray in the genus Clymenia', the pterygoids appear to resemble those 
of the present species; the skull, however, cannot be confounded with it, as it is much 
smaller, has a broader and shorter rostrum, and less numerous teeth. 
1 Synopsis, p. 6. 
