SYSTEMATIC POSITION OF THE GENUS ARTAMUS. 
transparent wings could be discovered ; the skin of a single large 
soft-like larva was observed. The insects must either have been 
powerfully triturated by the action of the stomach, or much broken 
by the bill of the bird. Cloaca apparently extending for an inch in 
length, oval, slightly dilated, but not very wide ; also filled with the 
hard parts of insects, passing through in that state. 
In Artamus leucorhynchus, which Mr. Blyth kindly remitted 
to us from Calcutta in spirits, the structure generally agreed with 
that of the Australian species. 
In the muscular arrangement of the sternum and pectoral de- 
velopment of these birds, compared with that of the Herundinidce , 
there is no great difference, according to their relative size, though, 
in comparison with Cypselus , where there is immense power, it is 
much weaker, particularly as regards the pectoral muscles. In 
like manner, the skeletons of Hirundo and Artamus resemble each 
other, differing from others of the Fissirostres in the structure of 
the sternum. In Cypselus , the sternum is remarkable for the 
depth of its keel, and in the broad posterior margins being entire, 
and without any fissure, allowing no space to be wanting for the 
support of the powerful muscles used in flight.* In Trogon , 
Halcyon , Pr ionites, Merops, Coracias, &c., the sternum is cha- 
racterized by less elevation of keel, and by great breadth of the 
posterior margins, but which have two fissures of considerable ex- 
tent. Between the swallows, again, and Artamus, except in regard 
to size, there is a great similarity; both have an elevated keel — 
both are nearly of equal proportional breadth — and in both the 
posterior margin has only one fissure, proportionally longest in the 
swallow. When all these parts are compared with those of the 
Fringillidm, the marked difference is in the narrowness of the 
sternum of the latter, particularly at its posterior end. 
In the muscles of the lower larynx, the sterno tracheals are as 
in Hirundo , very weak and slender. 
The tongue resembles that of the Fissirostres, while the struc- 
ture of the intestinal canal is essentially that of an insectivorous 
bird, more so indeed than in Hirundo. The stomach, in A. leuco- 
rhynchus, is stronger and more muscular than in A. sordidus ; in 
* It is curious, that the nearest resemblance to the sternum of the Swift is found 
in that of Procellaria pelasgica — the more curved or boat-like appearance of which, 
however, tells that it belongs to an aquatic type. 
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