214 EDWIN CHAPIN STARKS. 



The maxillary elements are of rather thin spongy bone rather 

 solidly and immovably attached to each other though not anchy- 

 losed. The premaxillary carries a single row of bicuspid teeth 

 (or tricuspid teeth if a scarcely developed third cusp be consid- 

 ered). The usual backward developed spine from the symphysis 

 of the premaxillaries is scarcely developed, and instead of slid- 

 ing over the vomer and ethmoid between the nasals, it abuts 

 against the shallowly concave front of the ethmoid. A short 

 process from each maxillary fits into a cup at the front of each 

 arm of the vomer, and the movement of the upper jaw is a 

 swinging motion from a hinge similar to that of the mandible 

 rather than the usual sliding motion. 



The opercular apparatus is complete and in no way peculiar. 

 The preopercle has an extra long lower limb extending forward 

 from its angle with the upper limb. The hyomandibular is long 

 and with a simple unforked head. It sends no process to the 

 metapterygoid, which occupies a position between the lower end 

 of the hyomandibular and the quadrate. The mesopterygoid 

 is very small but in the usual position between the metapterygoid 

 and palatine and connected with the pterygoid below. The 

 symplectic is small and slender and runs along the inner surface 

 of the quadrate. The pterygoid and palatine are normal in 

 arrangement, the latter attached to the lower edge of the pre- 

 frontal, but anterior to the palatine is a prepalatine bone. This 

 is a cylindrical -shaped bone, suturally, but not immovably at- 

 tached to the front of the palatine and extending anteriorly along 

 the side of the vomer to the upper edge of the maxillary, very 

 much as the anterior process on the palatine in the majority of 

 spiny-rayed fishes does. 1 



The mandible is short and resembles the united maxillary bones 

 in shape. The articular is very small and is almost covered from 

 sight by the dentary. A small angular bone is present. The 

 mandibular teeth are in a single row and similar to those on the 

 premaxillary. 



The suborbital chain is complete, but no suborbital shelf ex- 

 tends inward around the orbit. 



1 In order to make sure that the possession of this unique prepalatine element was 

 normal three different specimens were examined. 



