" AQUINTOCUBITALISM " IN THE BIED's WING. 247 



inwards on to the ulna — ousting the cubital remiges 1-3. Next, 

 the remiges of Digit II. moved inward on the ulna. Originally 

 there were five of thes^, but the 5th, lying in the carpal angle 

 between the bases of Metacarpals III. and IV., became sup- 

 pressed, — -just as occasionally happens in the case of the " carpal 

 remex." The coverts of this suppressed 5th remes were retained. 

 Feathers 1-4 only remained to migrate on to the ulna. The 5th 

 is now only indicated by its coverts, — hence the diastataxic wing. 

 The carpal covert and remex of existing birds represents the short 

 1st remex and coA^ert of Digit III., which has travelled inwards 

 along Mc. III. to rest finally on the carpal joint at the base of 

 Mc. II. 



Exceptions. 



The wings of all birds are either eu- or diasta-taxic. More- 

 over, there is no known exception to the rule that, though a 

 genus may include both forms of wings, it will be found that 

 the species constituting that genus will group themselves, in- 

 variably, into two sections — those with eu- and those with 

 diasta-taxic wiugs ; for, as yet, individual variation in this 

 particular is unknown. Therefore, the wing of any given species 

 being found to be diastataxic, it may be certainly predicted that 

 every individual of that species will also be diastataxic, and 

 vice versa. 



Amongst the Carinatae there are certain large groups every 

 individual member of which, so far as is known, has diastataxic 

 wings. These are : — 



Pygopodes = Divers, Grebes. 



Tubinares = Petrels, Albatrosses. 



Herodiones = Herons, Storks. 

 Steganopodes = Cormorants, Grannets, Prigate-birds. 

 Phoenicopteres = Plamingoes. 



Anseres = Swans, Ducks, G-eese, Screamers. 



Accipitres = Eagles, Hawks, Vultures, and Secretary- 



bird. 

 Halli = E.ails. 



Limicolse = Curlews, Plovers, Sandpipers, Auks, Gulls. 



Pterocletes = Sand-Grouse. 



Megapodes = Mound-builders. 



