Zoological ^society. 525 



Halodroma, and others, that the presence or absence of the hmd-toe 

 in birds becomes, under certain circumstances, a character of very 

 small value in the natural arrangement. The fact seems to be, that 

 when in any group the hind-toe becomes so slightlj^ developed as to 

 be unable to perform those functions of prehension or of progression 

 which are its usual duties, the transition from the abortive state of 

 this organ to its total disappearance becomes ver\' unimportant. In 

 the group of the Plovers too much weight has hitherto been attached 

 to the presence or absence of the hind-toe ; it has been made the 

 groundwork of divisions into families and subfamilies, whereas the 

 utmost value that can justly be assigned to it amounts only to that 

 of a generic character. This is proved by the fact that the absence 

 of the hind-toe is not coincident with the other and more extensive 

 changes of structure in the group, so that it becomes indicative of 

 analogy rather than of affinity, as the following table of the genera of 

 CharadriancE will show : — 



A. Acrotarsia reticulate, wings pointed, plumage spotted. 



Three-toed Charadrius. 



Four-toed Squatarola. 



B. Acrotarsia reticulate, wings pointed, plumage black, white, and 

 grey, in large masses. 



Three-toed .... Eudromias . Hiaticula. 



C. Acrotarsia scutate, wings rounded, plumage black, white, and 

 grey, in large masses. 



I. Face unwattled. 



Ca. wing-spine short. 

 Three-toed. . Philomachus, Mcehr. J P. coronatus (Gm.). 

 (Hoplopterus, Bon.) ] b. wing- spine long, 



(^ P. sphwsiis (Linn.). 



Ca. wing-spine short, 



T-, , , T7- 77 Ti ] V. cristatus (Linn.), 



rour-toed .. Vanellus, lemm. < 7 • • r 



I b. wmg-spme long, 



[_ V. cayennensis (Gm.). 

 IL Face wattled. 



Three-toed Sarciophonis, mihi. 



Four-toed Lobivanellus, mihi. 



The last two groups which have hitherto been united, the one 

 with Charadrius, the other with Vanellus, are now for the first time 

 defined. 



Genus Sarciophorus*, n. g. 



■<: Charadrius, Gm. 



DifF. Char. — Three-toed, lores wattled. 

 Rostrum ut in Charadriis. 



Membrana loris affixa, nuda, erecta, in anticum protensa. 

 Ala elongata;, caudam vix superantes, remigibus tribus primariis 



subscqualibus. Spina pollicaris brevis, obtusa. 

 Cauda modicaj longitudinis, rectricibus aequalibus. 



* Sapici'ov, a caruncle ; ipepw, to bear. 



