Skull of an Embryo Cliioiiarchus. 317 



the adult because the birds possessing it are exposed to the 

 same influence of salt water to a greater degree than the 

 generality of Waders. 



When going through the osteology of the Ducks, I noted 

 the fact that most, if not all, sea Ducks had large supra- 

 orbital depressions and consequenth^ large supraorbital 

 glands. In fresh-water Ducks the grooves were quite 

 inconspicuous. Subsequently I found that Mr. Pycraft 

 had noted the same interesting fact. It seems reasonable 

 to conclude that the internal secretion of these glands may 

 counteract in some way the adverse effect which salt water 

 might have on the bird's plumage. 



(4) In the adult Sheath-bill the antorbital plates are 

 non-existent, or, at least, only the smallest relic of them 

 ossifies and remains evident. In the embryo they are 

 represented by a quadrangular plate of cartilage, which, in 

 form and shape, as well as in its relations to the descending 

 process of the lacrymal, is quite characteristically pluvialine. 



The manner in which the descending process of the 

 lacrymal joins the antorbital plate in the embryo is also 

 quite pluvialine. 



Summary. — All these points, in as far as they go, confirm 

 the belief assumed in my paper on the Sheath-bills that 

 these birds are pluvialine. 



V. Some Notes on the Crab-Plover 

 {Dramas ardeola PaykuU). 

 Dramas is such a peculiar and aberrant Charadriiform type 

 that any fresh crumbs of knowledge that can be gleaned 

 about it seem worth noting. If there is anything in this 

 ])aper worth recording, it is entirely due to the trouble which 

 Dr. Drake .Brockman took in procuring for me, through Mr. 

 J3ethel,an adult bird and two nestlings from the Somaliland 

 Protectorate. These were preserved in spirit, and arrived 

 in England in excellent condition. Although the process"^ 



* A small liole is punctured exactly in the mid-line of the abdomen ; 

 the birds are immersed in spirit for one or two days, then taken out and 

 ■wrapped in rags soaked in spirit, and then packed in a biscuit-tin, the 

 lid uf which is soldered down. 



