288 DIXPEINIBJ!. 



" The orbital plate of the palatine sends off an outer thin lamina, 

 which terminates by a free margin at the back of the orbit. The 

 palatine plates of the maxiUaries unite together for about an inch 

 in front of the palatines, then slightly diverge to give place to the 

 vomer, which, however, does not sink to their level : in advance of 

 the vomer the plates slightly diverge to their anterior ends, giving 

 place to the prcmaxUlaries, which form the apex of the muzzle. 

 The rest of the disposition of the maxiUaries accords with Cuvier's 

 account in Phoccena glohieeps. The superorbital plate is divided by 

 a notch from the rostral part of the maxiUary, and forms a tuberosity 

 articulated with the underlying malar (26). 



" The premaxillaries (22) accord equally with those in Phoccena 

 glohieeps, save in their shorter proportions concomitantly with those 

 of the maxiUaries and of the muzzle. They are perforated near the 

 outer margin, between the posterior and middle third, the canal 

 leading forward and inward : the three perforations in the maxillary, 

 external to the nasal portions of the premaxiUary, are of canals which 

 converge to open in an oblong fossa beneath the fore part of the roof 

 of the orbit. 



" The pterygoid is a large, sinuous plate, folded upon itself £pom 

 within upward, outward, and backward : the thick fore paxt articu- 

 lates with the palatine, whence it continues the bony roof of the 

 mouth backward for the extent of 1" 8'", with a convex surface, 

 divided from its fellow by a vacancy of 8'" breadth, exposing the 

 presphenoid and vomer : the inner plate of the pterygoid forms the 

 outer wall of the lower part of the nasal passage, and continues that 

 passage obliquely backwards, as an open canal, beneath the base of 

 the alisphenoid (6), as far as the otocranial plate of the basisphenoid 

 (5'). This posterior production of the pterygoid is three -sided: the 

 inner or narial one is concave ; the outer one is also concave, forming 

 a channel leading upward and forward to the orbit ; the upper facet 

 is sutural, and articulates with the basi-, pre-, aJi-, and orbito-sphe- 

 noids. The anterior external lamina of the pterygoid bends outward 

 and upward to articulate with the corresponding free lamina of the 

 palatine (r), bounding the narrow and deep sinuous fissure between 

 the outer and inner portions of both bones. 



" The malar (26), as in other Delphinidee, consists of the antorbital 

 and styliform (26) portions. The former is a narrow triangle with 

 the base thick, convex, turned forward, underpropping the ftire part 

 of the superorbital plate of the maxillary (21"), and articulating with 

 the same part of the frontal ; the apex extends backward, and is 

 wedged into the roof of the orbit between the frontal and maxillary. 

 The styliform portion (26) is given off by a process extending inward 

 (mesiad), at right angles to the antorbital portion j and a few lines 

 behind its fore part it suddenly contracts, and extends backward, 

 with a slight upward bend, to the squamosal, articulating by a con- 

 cave, oblique terminal facet to a tubercle at the fore and under part 

 of the zygomatic process of the squamosal (27) ; the length of this 

 part of the malar is 3", its thickness throughout the greater extent 

 is 1^'" by 1'"; its squamosal articulation is 4'" across. The form of 



