94 ALLEN 
L.Ven.F.V.) instead of uniting with the right ventral fin vein 
to form the right ventral vein, forms the principal venous sup- 
ply for the left ventral vein. 
In Hexagrammos and Scorpenichtys the ventral veins are 
essentially the same as the last case described under Ophzodon ; 
namely, the 2 ventral veins are of equal size, receiving their 
venous supply from the right and left sides respectively. In 
Scorpenichthys, however, the right and left ventral fin veins do 
not leave the ventral fin ray canal with the artery from the last 
ray, as is the case with Ophzodon and Hexagrammos, but may 
leave the canal between any 2 rays, usually, between different 
rays in the 2 different fins. In Sebastodes these 2 veins are of 
equal size, but another condition is introduced. The 2 ventral 
fin veins leave the ventral fin canal with their respective 
arteries, anastomose, and the common trunk thus formed passes 
cephalad parallel with the ventral artery, between the two pelvic 
bones, and usually empties into the left ventral vein. 
5. Subclavian Veins. 
In Ophiodon there are 3 subclavian veins, returning the 
venous blood from the region of the pectoral arch. Two of 
these, coming from the outer or abductor muscles, unite in 
forming the subclavian sinus which empties into the sinus veno- 
sus in front of the precava, while the third one coming from 
the rays and the inner or adductor muscles, pierces the anterior 
fork of the kidney. This vessel does not empty directly into 
the cardinal trunk, but first breaks up into smaller vessels, 
which reach the cardinal through the renal veins. 
Internal Subclavian or Subclavian Veins,,, (Pl. Il, fig. 14; 
Sub.V..,,).—The vessel thus designated, in the main, cor- 
responds with the internal subclavian artery. It receives its 
supply in part from the pectoral rays, and in part from the ad- 
ductor muscles, situated on the inner side of the pectoral arch. 
This vessel has its origin from a dorsal and a ventral pectoral 
fin vein, which unite in the pectoral ray canal, thus forming a 
continuous vessel, which runs along behind the corresponding 
pectoral fin artery. Within this canal it receives a small vein 
returning the venous blood from each ray. In no 2 specimens 
