BLOOD-VASCULAR SYSTEM OF THE TILE-FISH. 



93 



curves laterad through a foramen .situated in the lower (ventral) end of the ceratohyal 

 near its dorsal border, continues along the lateral or cranial surface of the ceratohyal 

 and interhyal and passes through a fissure between the caudal angle of the quadrate 

 and the dorsal end of the symplectic, still occupying a position lateral to the bones; 

 then passes dorsad through a fissure between the ventral end of the hyo-mandibular 

 and the metapterygoid and continues dorsad along the inner surface of this bone 

 until it reaches the pseudobranch". 



The following an 1 its branches: 



a. A vessel at the ventral end of the Hist branchial arch which divides into the 

 nutrient artery to this arch (5, fig. L6) and into branches which go to the cranial part 

 of the niusculus sternohyoideus.'' (.£, fig* L6.) 



Fig. 6.— Efferent branchial vessels of tile-fish, with circulus cephalicus. Ventral aspect, natural size. On the 

 left side the hyoidean and direct afferent pseudobranchial arteries are shown; on the right side the efferent 

 pseudbbranchia] artery. 



b. An anterior and a posterior branch shortly after passing through the fora- 

 men at the ventral end of the ceratohyal. The anterior branch (6') corresponds to 

 the lingual artery of Wright (1885) and supplies the niusculus geniohyoideus and 

 structures on the floor of the mouth; it terminates in two vessels which accom- 

 pany the rami of the dental bone. The posterior branch (?) is somewhat smaller 

 than the anterior and runs caudad over the lateral surface of the ceratohyal to 

 supply the branchiostegal region. 



c. Two branches where the artery passes through the fissure between the quad- 

 rate and symplectic; the larger/anterior branch (8) runs craniad and divides into 



"The pseudobranch of the tile-fish consists of from 10 to 50 filaments, and occupies a position on the medial side of 

 the dorsal end of the hyomaiidilatlar; its filaments arc parallel (o the most dorsally situated filaments of the first Kill 



'■For tin' muscular system the writer has followed the terminology of Allis (1897), and for the hones that of Reynolds 

 I 1897) and Parker & Haswell (1S97). 



