300 MR. F. E. BEDDARD ON THE [Feb. 18, 
by the late W. A. Forbes, upon the dissection of which the following 
notes are based. 
As to external characters, the pterylosis offers no salient point 
of difference from that of the Gulls as described by Nitzsch. The 
oil-gland is tufted. There are 12 rectrices. The bird is aquinto- 
cubital. As regards the alimentary viscera the most important 
fact to comment upon is the rudimentary and nipple-like character 
of the ceca. 
The tensores patagii are illustrated in the drawing exhibited 
(woodcut, fig. 1). They are exactly like those of Rissa tridactyla, 
Fig. 1. 
ET 
ere 
Muscles of the patagium of Rhynchops. 
t.p.l., tendon of tensor patagii longus ; t.p.b., tensor patagii brevis; B. its wrist- 
ward slip; F, patagial fan; A, tendinous threads on ulnar side of arm. 
of which I possess a drawing by Mr. W. A. Forbes. There are 
two tendons to the tensor brevis, of which the anterior is for the 
greater part of its length made up of three separate strands. The 
hinder tendon is much slighter. The anterior tendon gives off a 
little way from the forearm a wristward slip (fig. 1, B), from which, 
where it joins the tendon of the extensor radialis metacarpi, a 
patagial fan (F) arises which joins the longus. This fan as well as 
the main tendon of the Srevis are continued over to the ulnar side 
of the forearm as a diffuse glistening tendon. From the point 
where the wristward slip of the brevis springs there is another con- 
nection with the longus, which is lettered A in the drawing (fig. 1). 
=_— Pe 
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