THE OSTEOLOGY OF AMIURUS CATUS. 303 
The foramen (for), however, which usually occurs between them, is 
still present and indicates that while the scapular portion is very 
small the coracoid has reached a very great degree of development, 
meeting with its fellow in the middle line, and being united to it by 
sutural union. This coracoid has been described (by Huxley for 
instance) as the clavicle, but this must be a mistake, for in a well 
macerated skeleton, this portion separates perfectly from the portion 
in front, the clavicle, showing that these two are not the same. If 
the extension of the coracoid, towards the middle line, seen, for 
instance, in the Gadide, be continued still farther, the arrangement 
which obtains in Amiwrus will result. The upper surface of these 
coalesced bones presents no point worthy of special notice, but on the 
ventral surface of the outer portion the following points may be 
noticed. First of all there is the bridge-like process (br) which 
extends over to the anterior ridge on the under surface of the infra- 
clavicula, and at its base a high ridge (r) is to be seen which dim:- 
nishes rapidly as it passes inwards, and is soon lost. Slightly exterior 
to this is a small rod-like process (rp), which articulates with the 
inner basalia of the fin, and from its base a fine spicule of bone (sp) 
passes transversely across to the posterior margin, its anterior portion 
giving an articular surface to certain of the radiaka. This spicule 
forms an arch through which a muscle runs and just below its 
anterior point of attachment is the foramen between the scapular 
and coracoid portions. 
From the arrangement of the articulations of the fin, and from 
general characters, I am inclined to refer to the scapula, the thin 
triangular portion, which is well marked off, and whose limit on the 
exterior edge would be a line drawn from the base of the rod-like 
process for the inner basale. The spicule-like arch belongs probably 
to the coracoid portion. 
The fin consists of two principal rows of elements. The proximal 
row consists of three elements, two osseous and one cartilaginous. 
The posterior element (the tin being erected) is osseous, a rather 
slender rod tipped with cartilage at either end. Proximally it does 
not reach the pectoral arch, a small cartilage intervening. This is 
Huxley’s' metapterygial basale. The next element, proceeding 
1 Hugley.—Anatomy of the Vertebrates. London, 1871. 
