— 135 — 



The supraorbital canal contains six sense organs, one lying in the nasal and five in tlie frontal. 

 As in Scorpaena. the fourth primary tube anastomoses in the middle line with its fellow of the 

 opposite side to form a frontal commissure, the penultimate tube anastomoses with the main infra- 

 orbital canal between the frontal and pterotic bones. and the primary tube between the fourth and 

 fifth organs of the line has been suppressed. 



The preoperculo-mandibular canal anastomoses at its dorsal end with the main infraorbital 

 canal between the pterotic organs that are innervated by the oticus lateralis and the supratemporalis 

 lateralis vagi. It contains eleven sense organs, four lying in the dentary, one in the articular and six 

 in the preopercular, as in Scorpaena, this being one more organ in the dentary and one more in the 

 preopercular than is found in Cottus. The next to the most dorsal organ in the preopercular was nearly 

 always a double organ. 



II. Trigia lyra. 



In Trigia lyra the granulations on the dorsal surface of the skull are considerably smaller than 

 in T. hirundo, and the Striae smaller and more numerous. This gives to the surface a sand-paper-like 

 feel and appearance. The preorbital part of the skull is beut downward somewhat more than in 

 T. hirundo and the skull is everywhere relatively taller than in that fish, excepting only in the anterior 

 half of the snout, where it has the same relative heiglit. On the posterior half of the dorsal surface 

 of the snout there is a large, low, median swelling. The interorbital portion of the dorsal surface of 

 the skull is but slightly concave, and there is, on either side, but one, short and stubby, preorbital 

 spine. The postorbital portion of the dorsal surface of the skull is decidedly convex in transverse 

 section, and slightly convex in median longitudinal section; and there is no slightest indication of a 

 subquadrangular groove. 



The rostral depression is relatively larger than in T. hirundo. The nasal rests definitely upon 

 the summit of the anterior palatine process of the ethmoid cartilage, the rounded antero-ventral 

 surface of the latter process articulating with a facet at the base of the maxillary process of the palatine. 

 The anterior edge of this facet on the palatine is raised to form an eminence which gives Insertion 

 to the rostro-palatine ligament, and this eminence, lying in front of the palatine process of the ethmoid 

 cartilage, fits in between the nasal above and the ascending process of the vomer below in such a 

 manner that it seems to form part of the articular contact of the palatine with this part of the skull. 

 The lateral edge of the nasal has a sliding articulation with the dorsal surface of the lachrymal, as in 

 T. hirundo. 



The ectethmoids suturate with each other in the middle line behind the mesethmoid, as Günther 

 has stated. The orbital surface of the bone includes the orbital surface of the bone in T. hirundo 

 and also that little surface that lies between the two posterior portions of the ridge along the lateral 

 edge of the ventral surface of the bone in the same fish. This condition thus being intermediate 

 between that in T. hirundo and that in Scorpaena. 



The median anterior eye-muscle canal, in the antorbital cartilage, so well developed in 

 T. hirundo, is here represented by what is little more than a perforation of the extreme anterior end of 

 the interorbital septum. From there a canal for the olfactory nerve runs forward on either side, this 

 canal being enlarged, as in T. hirundo, to form a deep and large recess in the bind end of the meseth- 



