562 tall. T. GOODEY OX THE SKELETAL [Mar. 15, 



As a rule the metapterygium is attached by ligament to the 

 cbracoid, but I have found one case in which the mesopterygium 

 interposes a short process between the metapterygium and the 

 coracoid and so prevents this attachment. 



The radials are for the most part trisegmental, but the last 

 two or three attached to the distal segment of the metapterygium 

 are, as a rule, without segmentation. In the smaller tins which 

 have been examined, two small post-axial radials are present ; 

 these are attached to the postero lateral edge of the mesopterygium 

 and are rot, as Garman figured them, in the same straight line 

 as the metapterygium. In the larger fins from the female 

 specimen, however, the two most distal radials of the meta- 

 pterygium are attached terminally and not post-axially to it. 

 The proximal segments of the radials attached to the meso- 

 pterygium exhibit fusion, and in most cases the resultant mass 

 of cartilage includes the first one or two of the proximal segments 

 of the radials attached to the metapterygium, as shown in fig. 18. 



In some cases the whole of the proximal segments do not fuse 

 as represented in the figure ; one or two may remain distinct. 

 Whatever amount of fusion is shown, however, the original 

 radials are indicated by lines of calcification in the fused cartilage. 



I have entirely failed to find the nerve foramen figured by 

 Braus (3) perforating the fused proximal segments to the radials 

 attached to the mesopterygium. 



VII. The Pelvic Girdle axd Fixs of the Female. 



'■' (Plate XLV. fig. 19.) 



. The pelvic girdle takes the form of a, flattened plate of carti- 

 lage, which is, as Garman pointed out, about twice as long a« 

 wide ; it is also equal in length to the proximal segment of the 

 basipterygium. On its anterior edge it has a median convex 

 protuberance, whilst its posterior edge is practically straight, 

 r.ot being nearly so concave as Garman has figured it. Its 

 lateral edge is almost straight, but has a few indentations, thus 

 presenting a difference from the curved edge figured by Garman. 

 A short distance from each side there is a row of foramina which 

 transmit spinal nerves ; the second from the anterior end is the 

 largest of these in all cases. In regard to these lateral foramina 

 it is interesting to note that there is a. certain amount of vari- 

 ability in their number in different specimens of Chlamydoselachus. 

 There is also a difference in the number of foramina for each 

 side of the girdle in one and the same specimen, as shown in the 

 accompanying table ::— . 



Specimen. 



Large female 



Male, Museum specimen ...... 



Male described in this paper... 



Braus (2) gives 6 foramina in his figure, Garman (10) gives 

 8 on each side in his, and Goodrich (13) gives 10 on each side in 

 his figure. ••-•■ 



