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the united lachrymal and palatine bones in a manner that will be described when describing those 

 bones. It may however here be stated that the two articulating surfaces do not seem to come into 

 close contact, being separated by a line of tough fibrous tissue which not only binds the bones stronglv 

 together but permits of a sort of swinging movement. The larger part of this articulation, such as 

 it is, is with the lachrymal, the articulation with the palatine being limited to the extreme anterior 

 end of the ridge, and the articulating surfaces there apparently Coming into closer contact than else- 

 where. The posterior half of the ridge is double, having mesial and lateral portions which diverge 

 slightly. The mesial portion is a direct posterior Prolongation of the anterior, articular portion of the 

 entire ridge, but it is low and narrow, and curving ventro-mesially vanishes near the hind edge of 

 the ventral surface of the bone. The other, lateral portion of the ridge is taller and more important 

 than the mesial one, and running posteriorly and slightly laterally, soon becomes continuous with 

 the posterior portion of the lateral edge of the bone. On the lateral surface of this portion of the 

 ridge the dorsal edge of the second infraorbital bone slides as the hyomandibulo-palato-quadrate 

 apparatus swings inward and outward. 



The anterior end of the ventral surface of the ectethmoid projects forward beyond the rest 

 of the bone as a thin flat process, of perichondrial appearance, which lies upon the ventral surface 

 of that lateral portion of the ethmoid cartilage that fornis the floor of the nasal pit; the lateral edge of 

 the process of the ectethmoid projecting slightly lateral to the lateral edge of the overlying cartilage 

 and so forming part of the floor of the nasal pit. The process extends forward onto the base of an 

 anterior palatine process of the ethmoid cartilage, its anterior end there being overlapped externally 

 (ventrally) by the small lateral process of the vomer. 



The anterior palatine process of the ethmoid cartilage is a pronounced eminence on the lateral 

 edge of the snout, bounded antero-mesially by the ascending process of the vomer, postero-mesially 

 by the mesethmoid, and posteriorly by the process, just above described, of the ectethmoid. Ventrally 

 it lies upon the dorsal surface of the body of the vomer, but projects laterally considerably beyond 

 that bone. With the latero-ventral surface of the process the palatine articulates. The summit of 

 the process always closely approaches, and is sometimes apparently in actual contact with, the ventral 

 surface of the lateral edge of the nasal, near its anterior end; this relation of the process to the nasal 

 varying considerably in different specimens. In most specimens a slight interval seems to separate 

 the two structures. 



The posterior, orbital surface of the ectethmoid lies at an angle to its ventral surface, the two 

 surfaces being separated by a sharp ridge. This ridge, or angle, corresponds to the orbital rib of my 

 descriptions of Scomber, and to a shglit ridge which, in Scorpaena, extends dorso-laterally from the 

 ventro-mesial corner of the orbital surface of the bone to the point of Insertion of the posterior ethmo- 

 palatine ligament. This latter ligament is, in Trigla, double, the two ligaments found partly fused in 

 Scorpaena, here being wholly and quite widely separated. One of these ligaments is a flat band which 

 has its origin on the ventro-lateral surface of the orbital ridge above referred to, and, running down- 

 ward and forward, is inserted on the palatine cartilage in a manner to be later described. The other 

 is a slender and delicate ligament which has its origin on the ventral surface of the ectethmoid and, 

 running downward and forward, is also inserted on the palatine cartilage. 



The orbital surface of the ectethmoid of Trigla thus corresponds to one half only of the sanie 

 surface of the bones of Scorpaena and Scomber. The other half of this surface must then be looked 

 for in what is apparently, in Trigla, the ventral surface of the bone, and it seems probable that it is 



