CRYPTURI. 447 
corpore toto subtus albido, fasciis marginalibus brunneis maculatim notato. Long. tota circa 9°5, ale 5:2. 
(Deser, av. jun. typ. ex San Blas. Mus. Brit.) 
Hab. W. Mexico, San Blas (Belcher 12).—N. Pactric, Japan 3, Kamtchatka 3, Aleutian 
Is, 3, 
This little Auk is an inhabitant of the coasts and islands of the North Pacific, being 
found in Japan, Kamtchatka, and thence to the Aleutian Islands. In the British 
Museum is a specimen said to have been obtained by Lieut. [afterwards Sir Edward] 
Belcher off San Blas, in Western Mexico!. Grayson also mentioned his having seen 
‘Guillemots ” at Isabel Island and off the Tres Marias group’. Mr, Nelson, during 
his visit to the latter islands, kept a sharp look-out for Auks or Guillemots, but 
without result 4, 
Order CRYPTURI. 
The Tinamous are exclusively Neotropical. In external form they somewhat resemble 
the Gallinz, but as regards internal structure and other features they differ in a marked 
degree from the true Game-Birds. 
The Crypturi have, until recently, been considered a distinct order belonging to 
the Carinate, since they possess a keel to the sternum, but differing from all the 
rest of the group in having a Struthious palate resembling that of the Ratite. By 
many naturalists, therefore, the Tinamous have been placed in the position of an 
intermediate link between the Struthious and the Game Birds. 
Mr. Pycraft has recently made a study of them, and considers that they are certainly 
more nearly allied to the Struthious Birds than to the so-called Carinate, the structure. 
of the palate being, in his opinion, of much greater significance than the presence or 
absence of a keel to the sternum. He has proposed, therefore, that the Class Aves should’ 
be divided into two great groups—the “ Paleognathe,” consisting of the Struthious 
Birds and the Tinamous, and the “ Neognathe,” to include all the remaining birds, this 
second group being equivalent to the Carinate without the Tinamous. 
According to him, the Palzognathz have the vomer and pterygoids directly connected 
by squamous sutures, while the palatine bones are widely separated from one another 
posteriorly, failing anteriorly to reach the palatine processes of the premaxilla. In the 
Neognathe the vomer is often wanting, and when present it is supported by the 
palatines, while the pterygoids take the form of short rods, articulating anteriorly with 
the palatines by means of a joint. 
The palate of the Crypturi is decidedly of the Palzognathous type, and is very similar 
to that of Rhea. In the character of the nestling-down the Tinamous appear to be 
unique. The aftershaft of the prepenne is as large as the main shaft; preplumulie 
are wanting; the definitive feathers may have a moderately large after-shaft, or this 
