— 95 — 



be explained below, the frontal spine has been displaced laterally to such an extent that it might 

 be mistaken for one of the lateral row of spines. 



The parietal spinous ridge and the transverse conimissural ledge bound laterally and anteriorly 

 a flat smooth median portion of the dorsal surface of the brain case, this surface lying at a slightly 

 lower level than the anterior part of the dorsal surface of the skull. This flat and slightly depressed 

 surface thus certainly represents a slightly developed subquadrangular groove on the Vertex of the 

 skull of the fish, notwithstanding that Günther ('60, vol. 2, p. 95) says that all members of this family 

 are without that groove. Posteriorly, this slightly developed groove is bounded by a slight transverse 

 ridge which lies on the dorsal surface of the parieto-extrascapular of either side, near its hind edge. 

 This ridge extends to the mesial edge of either parieto-extrascapular, but as these bones do not meet 

 in the middle line, the ridge does not extend entirely across the hind edge of the skull. The ridge 

 marks the course of a portion of the supratemporal commissure, the median portion of that commissure 

 lying in the dermal tissues, between the ridges of opposite sides, in a slight groove on the flat dorsal 

 surface of the supraoccipital. The slightly depressed surface that represents the subquadrangular 

 groove is thus not bounded posteriorly by a complete ridge, as in Scorpaena, simply because the 

 median portion of the supratemporal commissure is not here enclosed in bone. 



The lateral row of spines is represented by five spines. The anterior spine of the row is the 

 preocular spine, lying on that edge of the ectethmoid that forms the anterior portion of the roof of 

 the orbit. The next two spines of the row are the supraocular and postocular ones, both of which lie 

 close together, one directly behind the other, on the dorsal surface of the roof of the orbit, near its 

 lateral edge, and immediately anterior to the frontal spine. In the specimen used for illustration the 

 postocular spine is bifid on one side of the head, and, anterior to the supraocular spine, there is a small 

 additional spine. The supraocular and postocular spines, as normally found, together with the frontal 

 spine form a short line of three spines lying close together and equidistant one from the other, and 

 they correspond in position to the supraocular, postocular and tympanic spines of Jordan & Gilbert's 

 diagram of the spines in Sebastodes. The frontal spine however belongs, as just above described, 

 to the middle row of spines and not to the lateral one. The remaining two spines of the lateral row 

 are small ones that hardly rise above the outer surface of the body, one of them lying on the hind 

 edge of the suprascapular and the other on the hind edge of the supraclavicular. On the pterotic 

 there is a ridge, but it does not end in a spine. 



The intermediate row of spines is represented by a small spine on the hind edge of the epiotic 

 process of the suprascapular, this spine lying slightly mesial to the suprascapular spine of the lateral row. 



The bones of the snout of Sebastes diiTer in no important respeet from those of Scorpaena 

 scrofa. The mesethmoid processes, as already stated, are shorter than in Scorpaena, and are directed 

 forward instead of upward and forward. The nasals are traversed by the supraorbital latero-sensory 

 canal, and are relatively larger than in Scorpaena. The lateral arm of the ectethmoid is not dif- 

 ferentiated from the wing of the bone, as it is in Scorpaena, the ventral edge of the wing being simply 

 thickened and giving articulation, by two articular surfaces, to the lachrymal and palatine. The 

 vomer has, on either side, an ascending process, which gives articulation, as in Scorpaena, by the 

 intermediation of a disk of semi-cartilaginous tissue, to the ascending process of the maxillary. The 

 maxillary has a right-angled ascending process and a ligamentary process, the former articulating 

 both with the premaxillary and the vomer, and the latter giving .support to the lachrymal and pala- 

 tine, as in Scorpaena. The rostral is more deeply grooved on its ventral surface than in Scorpaena. 



