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viewed from above, but this is largely due to the marked elongation of the brain case; for the fossa 

 extends from the bind end of the skull about halfway to the postorbital process, which is about its 

 normal length. At about the middle of its length the fossa is bridged by the narrow and tubulär, 

 mesial one of the two lateral extrascapular ossicles found in this fish. Posterior to this bridge, the 

 central portion of the fossa is without roof, its mesial edge being slightly overhung by the lateral 

 edge of the epiotic, and its lateral edge being roofed by the lateral one of the two lateral extrascapular 

 ossicles. Anterior to the bridge, the fossa is wholly without roof. The posterior opening of the fossa 

 is roofed, as usual, by the suprascapular and the suprascapular process of the epiotic. The fossa 

 thus opens on the dorsal surface of the skull by two large openings. In the mesial wall of the posterior 

 portion of the fossa there is a pronounced preepiotic recess. 



The SUPRATEMPORAL FOSSA is as in Scorpaena, but much smaller. 



There are, as is well known, three SPINES on either side of the dorsal surface of the skull, 

 and one on the supraclavicular. The three spines on the dorsal surface of the skull form a row that 

 corresponds to the mesial row of spines of Scorpaena, the supraclavicular spine being the only one 

 of a lateral row. 



Of the three spines that form the mesial row, the anterior one lies on the dorsal surface of 

 the hind end of the nasal, and, projecting backward, overhangs the opening of the second primary 

 tube of the supraorbital latero-sensory canal. The next posterior spine of the row lies on the dorsal 

 surface of the frontal, and its relations to the supraorbital canal show that it is a frontal spine. It 

 lies, however, near the postorbital corner of the frontal, considerably anterior to its hind edge, this 

 Position thus differing considerably from that of the frontal spine in either Scorpaena or Sebastes. 



The base of the spine, in Cottus, overlies that part of the supraorbital canal that lies 

 between the fifth and sixth tubes of that line, and projects backward toward the seventh tube or 

 between that tube and the fifth tube. The sixth tube anastomoses with the main infraorbital canal, 

 and it was double in each of the two specimens examined, the fifth tube being also double in one 

 specimen. There is no spinous interorbital ridge related to the frontal spine. 



From the base of the frontal spine a strong ridge begins, the occipital ridge of Jordan and 

 Evermann's ('98) descriptions, and running backward in a curved course across the posterior portion 

 of the frontal and then across the parieto-extrascapular, ends, at the hind end of the latter bone, 

 in a stout spine. This spine lies partly above but mostly posterior to the supratemporal canal, its 

 Position thus not definitely indicating whether it is a parietal or a nuchal spine. It is however, in all 

 probability, a spine developed in relation to the parietal bone, and hence a parietal spine, the ridge 

 that terminates in it then being a parietal ridge. 



The parietal ridges of opposite sides lie relatively widely apart, and that part of the dorsal 

 surface of the skull that lies between them is flat, and corresponds to the subquadrangular groove 

 on the Vertex of Scorpaena; but here, in Cottus, there is, aside from the presence of parietal spinous 

 ridges, no indication whatever of a groove; for the region is not depressed and there are no anterior 

 and posterior bounding ridges whatever. 



The supraclavicular spine projects posteriorly from the dorso-posterior corner of the supra- 

 clavicular, ventral to the section of latero-sensory canal that traverses the bone. 



The MESETHMOID is, in all my specimens, a relatively delicate bone that extends but slightly 

 into the underlying cartilage. It has, on either side, a short stout mesethmoid process which is directed 



