262 DE. W. G. KIDEWOOD ON THE 



in number. The articular does not rise very high, and forms no 

 part of the corouoid process. The endosteal articular does not 

 appear to be readily separable from tlie ectosteal articular ; 

 there is a small sesamoid articular. The angular bone is distinct 

 from the articular, and forms the lower part of the articular facet 

 for the head of the quadrate. 



Hyopalatine Series (fig. 10). — The hyomandibular articulates 

 with the cranium by two barely separated heads, the anterior of 

 which is smaller than the other and rises higher. The opercular 

 head is stout. The hyomandibular enters into sutural relatioa 

 with the preopercular as well as the metapterygoid along its 

 ventral edge; it sends a slender process forward to meet the 

 entopterygoid. As in Osteoglosswn, a lateral process of the 

 parasphenoid articulates with the back of the entopterygoid just 

 beneath this process of the hyomandibular. The part of the 

 entopterygoid that lies below and in front of the articulation 

 carries an oval patch of crowded teeth, straight and rather blunt. 

 It is worthy of note that Valenciennes alludes incidentally to 

 this articulation between the hyopalatine arch and the para- 

 sphenoid (Hist. Nat. Poiss, xix. 1846, p. 471). 



The ectopterygoid is slightly curved, aud is not continued 

 down the anterior edge of the quadrate. The relations of the 

 palatine are rather strange, for the entopterygoid and ectoptery- 

 goid both extend to the anterior end of the hyopalatine arch, while 

 between their anterior portions, and confluent with them, lies an 

 extremely delicate membrane-bone, apparently to be identified as 

 the palatine, bearing on its upper surface, at some distance from 

 the front, the conical endosteal palatine. The palatine and 

 ectopterygoid are edentulous. 



Opercular Series (figs. 9 aud 10). — The opercular boce is of 

 average size and shape. The subopercular is wanting on both 

 sides in the specimen under observation, but it is important to 

 note that Yalenciennes (Hist. Nat. Poiss. xix. 1846, p. 470) has 

 described asmall subopercular in the following terms : — " Le sous- 

 opercule est represente ici par une toute petite piece osseuse, 

 mince comme une ecaille et situee dans le petit espace angulaire 

 que laissent entre eux I'opercule et le preopercule. J'iusiste 

 sur la petitesse de cet os, parce qu'il est tres-facile de I'enlever 

 et de le perdre dans I'epaisseur du bord membraneux de I'opercule 

 en preparant le squelette du poissou, et j'avertis qu'il faut I'avoir 

 vu sur le squelette pour le retrouver sur le jioisson desseche." 



The branchiostegal rays are eight in number on each side. Of 



