20> nu. \v. n. i;iPi;\vooi'' on rui: okam\i. ostkoi.ogv op 



'JVmpOfujl <ind Preopercular Series {WiX^. IS and '2'2). — Tho posst- 

 temporftl consists practically of its two limbs, thero being no 

 body to speak of. Tlie upper limb is long, and its extremity is 

 loosely attacbcd to the upper siu'tace ot" the epiotic; the lower 

 is short, and is attached about halfway along the iipper surface 

 of the opisthotic. Although the supertieial portion of the lower 

 limb carries a ticusory tube, ihe deeper portion of it must 

 obviously, from its relation to the opisthotic boi\e, be regarded 

 as the opisthotic limb. There may, in fact, be defected an 

 indication of a separation into a n\ore supertieial and a dee[Hn" 

 part at the posterior eud of the limb. The suprateniporal is 

 remarlvably large. It is a triangular curved lamina of bone 

 Avhich conceals the whole of the parietal, and parts of the frontal, 

 squamosal, epiotic, and supraoccipital. The t>vo suprafemporals 

 meet, or nearly meet, in the dorsal median line. The lower 

 portion of the preopereular is large, and extends luuch lower 

 than the siibopercular. The interopereular is long and narrow, 

 stretching from the front of the subopereular to the baelc of the 

 mandible, so that it is considerably above the level of the lower 

 edge of the preopereular. 



drcumorhital Series (Hg. 1S\ — There are nine bones ot' this 

 series. The nasal is small and narrow, and the two postorbirals 

 are large, and overlap the upper part of the preopereular. 



Maa^illari/ Serits (^tig. 1S\ — The gape isi bouiuied above by 

 l)oth maxilla and premaxilla, and the premaxilla is excepTiotuilly 

 long. In a roughly prepared skiill the maxilla appears to follow 

 on immedifvtely behind the posterior end of the premaxilla, but 

 it really extends some distance forward along the im\er surface 

 of the premaxilla, and is thus oA'erlapped by the premaxilla as it 

 is in so many Malacopterygian t5shes. l^nh premaxilla and 

 maxilla carry a sitigle row of teeth, those of the preninxilla beiug 

 larger than those of the maxilla. Tl\ere are no heads, either 

 of the premaxilla or the maxilla, for articulation witli the 

 ethmoid region of the cranium, and the articulation with the 

 palatine is of the feeblest character. There is no surmaxilla. 



JldiiJibiilar Series (^tigs. IS and '2'2). — The mandibular ramus 

 is long and narrow, and the eoronoid process low. The articular 

 is small as compared with the dentary ; its ectosteal and end- 

 osteal eoustitueuts are clearly distinct, and a suture between 

 the two appears on the external face of the ramus, which is 

 very tiuusual i^tig. ISX The sesamoid articular is comparatively 



