XIX 



I have likewise repeatedly observed the same arrangement 

 in the "uings of young sparrows and chickens. 



Having thus established the value of the carpal covert as 

 that o£ a true major covert, it becomes necessary to inquire 

 further into its frequently abnormal position, for it is some- 

 times ultimately attached to the proximal side of the 1st 

 metacarpal remex_, as already mentioned. We have seen, 

 however, by the test of microscopical examination, that on 

 the metacarpus the metacarpal coverts grow distally to their 

 respective remiges. Hence it follows that the 1st metacarpal 

 remex is not "without its own major covert, as ]\]r. Wray 

 imagined, although the carpal covert often assumes the 

 position of a true major covert to the 1st metacarpal I'emex, 

 especially when it is found closely attached to the latter. 



My next step was to inquire into the practical utility and 

 origin of the carpal covert. An analogous case of sup- 

 pression seemed to me to exist in the 5th cubital remex, 

 w liich is absent in several groups of birds, a phenomenon 

 for which no satisfactory explanation has been offered up to 

 the present time. To this the name of " aquincubitalistn " * 

 has been given and accepted, in contradistinction to ^'^quin- 

 cubitalism," the condition when the 5th cubital i^emex is 

 always present. Like Mr. Wray, I have also never found 

 a single trace of a 5th remex in a vestigial form, though I 

 fully believe in the possibility of such a discovery, when 

 complete material is at hand for examination t- 



In aquintocubitalism the presence of both an upper and a 

 lower wing-covert, together with the relative distance between 

 the 4th and 6th, leaves not the slightest doubt as to the 

 5th remex being missing. The carpal covert, accompanied 

 as it is by a feather which lies beneath it, and which varies 



* Dr. Gadow in Bronn's 'Thier-Reichs/Aves, anatomisclieThei], p.o57, 

 wi'ites " aquinilo-" and " quinfocubital,"' vfhicli is perhaps preferable. 



t [Up to the present time the mystery of "aquintocubitalism'' re- 

 mains uusohed. Whether the investigation upon which I am now 

 engaged wUl lead to anything remains to be seen, but just now I am 

 rather sanguine of success : suffice it to say, I do not think it will ever 

 be found in a " vestidal condition." — W. P. P.] 



B 2 



