1922.] Character.^ in some Charadr'iine f/enera. 479 



rim, being continued forwards and inwards in a smooth 

 and somewhat noticeable convexity in a manner somewhat 

 reminiscent of ]^aneUus (text-figs. 10 J & 11 b). 



(b) The interorbital space presents very distinct differences 

 in the two forms. In Sqnatarola it is narrower both actually 

 and relatively, while the raised corniced and everted orbital 

 rim so characteristic o^ Pbirialis is not present; moreover, 

 the grooves for the supra-orbital glands are not nearly so deep 

 or defined as in Plurialis, and the oeneral arrangement here 

 is Larine or Tringine (text-figs. 10 b & lib). In Squatarola 

 there are no anterior foramina caiidad of the lacrymals. 

 They are well marked in Pluvialis, and this seems to be a 

 Charadriine character. In Squatarola the inner margins of 

 the grooves for the supra-orbital glands meet in the middle 

 line of the vertex, forming a prominent sagittal ridge 

 down the centre. In Plurialis there is a fairly broad and 

 clearly-marked smooth median depression down the centre 

 of the interorbital space, which is not encroached upon by 

 the supra-orbital grooves. 



[(•) Turning to the palatal plates, we find in Squatarola 

 that the postero-external angle is rounded off (in some 

 specimens much cut awayj. In Pluvialis the angle is 

 squarer. 



(d) In Squatarola the ectethmoid or antorbital plate is 

 somewhat triangular in forin, the extero-inferior angle 

 representing the apex. In Plurialis the antorbital plate 

 has a quadrilateral form *. 



{p) In Squatarola the descending process of the lacrymal 

 falls perpendicularly to just touch the apex of the antorbital 

 plate. In Pluvialis it runs along the outer margin but does 

 not fuse with it. 



(/) Turning to a comparison of the maxillo-palatines, we 

 find that in the two forms under discussion these are not 

 identical. In Squatarola they appear to be more closely 

 applied to the pre-palatals, their posterior or free points 

 being little separated from the palatal plate. In l^luvialis 



* This, at any rate, is evident in perfectly o^sitied examples. 



