SKELL Y- SKIMMER 867 



Toe ; but in Cypselus the number never exceeds 3, being reduced 

 during embryonic development. The proximal phalanx of the 

 fourth toe is resorbed, while the 2nd and 3rd phalanges of the 

 third toe, and the original 3rd and 4th of the fourth .fuse together 

 respectively. The same number of phalanges obtains in Pany- 

 2Mla. Further reduction in the number of toes begins with the 

 hallux, which, as maj'' be gathered from Avhat has been already 

 stated, represents almost every intermediate condition from being 

 the strongest, as in AccipUres, to total loss. The second toe is 

 absent in Struthio only, though its malleolus is present, but in a 

 very degenerate condition. This Bird indeed seems to be on the 

 way to becoming one-toed, for though the fourth still exists, long 

 and functional, its phalanges decrease in length and strength towards 

 the extremity, and the terminal one is frequently reduced to a mere 

 nodule, devoid of a claw. Such an example has therefore already 

 reached a one-hoofed condition. Cholornis, a rare form from Thibet, 

 of doubtful affinity, seems to offer the only instance of the loss of 

 the fourth toe, which is said to be reduced to a mere stump. The 

 proportional length of the phalanges, especially when the reduction 

 in length affects the basal and next following phalanges without the 

 terminal, is of some taxonomic value, for a special account of which 

 reference may be made to the account in Bronn's Thier-reich (pp. 

 508-521), but above all to Kessler's Odeologie der Vogelfusse, in 

 the Bulletin of the Naturalists' Society of Moscow for 1S41 (pp. 

 467, 628). 



SKELL Y, or Shelly, a local name for the Chaffinch. 



SKIDDAW, another form of KiDDAW (see Guillemot). 



SKIDDY, otherwise SKITTY-Cock, a name applied to the 

 MoOR-HEN and Water-RAIL. 



SKIMMER, the English name bestowed by Pennant^ in 1773 

 on a North -American bird which had already been figured and 

 described by Catesby 

 (B. Carol, i. pi. 90) under 

 that of " Cut-water," — 

 as it appears still to be 

 called on some parts of 

 the coast,^ — remarkable 

 for the unique forma- 

 tion of its bill, in Avhich Rhynchops. (After Swauison.) 

 the maxilla, or so-called upper mandible, is capable of much vertical 



' "I call it Skimmer, from the manner of its collecting its food witli the 

 lower mandible as it flies along the surface of the water" {Gem. 0/ Birds, p. 57). 



- Other English names applied to it in America are "Razorbill," " Scissor- 

 bill," and '"Shearwater." 



