GREGORY: FISH SKULLS 



271 



the case. Figures 145, 146 show that in many details Anabas is more like the cyprinodonts 



than is Ophiocephalus. ^ . ^ , . . tt- ^ xt„ 



The dried skull (Fig. 147) of the gourami {Osphronemus, Bnt. Mus. Nat. H.st., No. 

 546) is chiefly notable for the parchment-like skeleton of the labyrinthine respiratory organ, 



fjl na 



Osphronemus 



Fig. 147. Osphronemus. Side view. 



Which lies in the upper part of the branchial chamber. The opercular ^^^-^^'^^^^^^^^^ 

 Anabas, except that the posterior border of the preopercular is barely, if at all, serrated. 

 The mouth is small and evidently protrusile. The median occipital crest is low^ 



According to Frost (1928^ p. 330), the otolith of Ophiocephalus lunus resembles that 

 of the ^.rcoJcentropomus except in certain details, while that of Anabas scandens resembles 

 the serranid type, except in details. 



Zeoidei (John Dory, Boar-fish, etc.) 

 The modern Zeus, according to the osteological investigations of Starks (IS^ is 

 related to the Ch^todontid^, although forming a very distinct family. Tate R^gan groups 

 the Zeid. with the Caproid. or boar-fishes in an order ^eomorphi coordinate in ank with 

 and placed between, the Berycomorphi and the Percomorphi. The Zeid^ ''^''^^lllt 

 vertebra, the Caproid. only 22. Nevertheless the ordina characters of the Zeomorphi as 

 defined by Tate Regan seem sufficient to connect the two families at the base of the Bery- 

 coidei. In the other direction they appear to be more or less related to the Ephippid., 

 which are classed by Tate Regan among the Percomorphi. ,^Uf\^^W 



The skull of Zeus (Fig. 148) is much compressed, with a small braincase relatively 

 large protrusile mouth, elongate prefrontal-vomerine region, which serves f^-" j^h^/^PP?^! 

 of the long ascending processes of the premaxillae. The latter also possess the articular 

 and nostmaxillary processes which are characteristic of percoid fishes. 



The protrusiUty of the mouth is probably responsible also for the marked upturning 



