Sni"i-Ki.i»r : ()srK()i.o(;\ oi nil. I ,imic()1..k. 23 



aborted in the Killdccr I'loNcr, where the descendini; process of the 

 the hu'r\inal is imu h broader and fuses more completely with the pars 

 plana. 



X'aryini,^ in si/e in the different species, the pars plana long remains 

 cartilaginous in the plovers, but eventually becomes a (piadrate osseous 

 partition, tjuite effectually separating the orbit from the rhinal cham- 

 ber. An irregular foramen for the passage of the nerves always occurs 

 above it, being very large in C/icinu/rii/s, owing to the comparatively 

 smaller si/e of its antorbital i)late. 



The vomer of the Mountain Plover is an extremely delicate and 

 elongated bone ; in front it runs out into a free and needle-like point, 

 while posteriorly it is bifurcated so as to articulate with the palatine upon 

 either side. It glides freely beneath the anterior pointed end of the 

 rostrum. 



Turning our attention to the pa/atiiie bone, we find that on either 

 aspect it forms the osseous roof of the mouth by sending forwards a 

 tapering prepalatine to anchylose with the maxillary and jiremaxillary at 

 their junction. The postpalatine portion of the palatine is expanded, 

 and it is separated from the fellow^ of the opposite side in front, where 

 the inner margin dips down to form the ''internal lamina" of the 

 palatine bone. Outwardly the bone is produced still further down to 

 form the " external lamina." The pterygoidal processes of the pala- 

 tines are in contact with each other, while the " ascending processes " 

 articulate with the forks of the vomer as already pointed out above. 

 The maxillo-palatines are elegant scroll-like lamin?e of bone, often per- 

 forated by a few foramina. Posteriorly, they do not normally come in 

 contact with the palatines on either hand, or with the vomer above 

 them. Anteriorly each l)one has two processes ; one, the stouter, 

 connecting it with the palatine ; the other, much more slender, with 

 the maxillary, while between the two a circular foramen is thus pro- 

 duced. 



In all our Plovers the zygoma is a very straight bar of bone, and 

 somewhat slender in its ])roportions. 



The superior jjeriphery of an orbit, formed by the frontal and nasal 

 of the corresponding side, is uniformly tilted upwards all along its con- 

 tinuity. Within this raised orbital rim, upon either side, we find the 

 well-marked depressions for the supra-orbital glands, pierced along 

 their bases by minute foramina, the largest perforation being at the 

 anterior end. In C. squatarola these glandular depressions pass be- 



