318 SHUFELDT. [VoL. II. 
of such fossze, either in the Surf-bird or among the Sandpipers. 
Actitus has a skull as free from any such depressions in its tem- 
poral region as the veriest Thrush that ever lived, and the same 
remark fully applies to our least Sandpiper and others of its 
genus. Another interesting point to notice in the cranium of 
A. virgata is the marvellous degree to which a tympanic cavity is 
exposed, as well as the external opening of the Eustachian tube 
within it. These parts seem to depend upon the large quadrate 
anteriorly, and the somewhat arching paroccipital process be- 
hind, for their protection, in so far as any osseous surrounding 
defence is concerned. 
This condition obtains in varying degree in the allied forms 
we have under consideration ; it being notably the case in Turn- 
stones and in Yematopus, though Plovers and Zringee are but 
little better off in this respect, perhaps the former of these last 
being the better provided of them all. 
And now, finally, turning to the nether aspect of the skull in 
Aphriza, we are at first struck with the diminutive size of its 
pair of pterygoid bones. These are short, compressed from 
above downwards, sharpened all along their anterior margins ; 
while behind they are characterized by strong basipterygoid 
processes, which articulate in the usual fashion with the facettes 
designed for them at the base of the sphenoidal rostrum. 
In the black Oyster-catcher, a pterygoid is no longer than the 
mandibular aspect of the corresponding quadrate is wide, and 
this statement holds true for the other skulls we have been ex- 
amining in connection with Aphriza. 
For the Plovers the pterygoids are well shown in Professor 
Huxley’s figure of Charadrius pluvialis,| although they are com- 
paratively much smaller in such a species, for instance, as C. 
squatarola, or others of our North American Charadriide. 
Upon comparing the palatines of A. virgata with those bones 
in the allied forms before us, we meet with several excellent dis- 
tinctive characters, especially when we include in this compari- 
son the maxillo-palatines. In Plovers, Sandpipers, Turnstones, 
and Oyster-catchers, the postero-internal angles or heads of the 
1 Ibid. P. Z. S., 1867, p. 427, Fig. 6. These bones are also represented in my figure 
of the base of the skull in the Mountain Plover (4. montana); Your. of Anat. and 
Phys. London, October, 1883, Pl. V., Fig. 3, Ag., where their relatively small size can 
at once be appreciated. 
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