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

 extends from tbe bind end of tbe skull about balfway to tbe postorbital process, wbicb is about its 

 normal lengtb. At about tbe middle of its lengtb tbe fossa is bridged by tbe narrow and tubulär, 

 mesial one of tbe two lateral extrascapular ossicles found in tbis fisb. Posterior to tbis bridge, tbe 

 central portion of tbe fossa is witbout roof, its mesial edge being sligbtly overbung by tbe lateral 

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

 ossicles. Anterior to tbe bridge, tbe fossa is wbolly witbout roof. Tbe posterior opening of tbe fossa 

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

 tbus opens on tbe dorsal surface of tbe skull by two large openings. In tbe mesial wall of tbe posterior 

 portion of tbe fossa tbere is a pronounced preepiotic recess. 



Tbe SUPRATEMPORAL FOSSA is as in Scorpaena, but mucb smaller. 



Tbere are, as is weU known, three SPINES on eitber side of tbe dorsal surface of tbe skull, 

 and one on the supraclaxacular. The three spines on tbe dorsal surface of tbe 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 bind end of the nasal, and, projecting backward, overbangs tbe opening of the second primary 

 tube of the supraorbital latero-sensory canal. The next posterior spine of tbe 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, bowever, near the postorbital corner of the frontal, considerably anterior to its bind edge, tbis 

 Position tbus differing considerably from that of the frontal spine in eitber Scorpaena or Sebastes. 



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

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

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

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

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



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

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

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

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

 Position tbus not definitely indicating wbether it is a parietal or a nuchal spine. It is bowever, in all 

 probabibty, 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. 



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

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

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

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

 and posterior bounding ridges whatever. 



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

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



The MESETHMOID is, in all my specimens, a relatively deUcate bone that extends but sligbtly 

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



