XXV 



TO demonstrate what I consider to have been the original 

 jDOsition of the remiges. 



The parts marked A and B represent digits II. and III. 

 respectively^ together with the scaphoid (radiale) and cunei- 

 form (iilnare) bones at their proximal end. It is assumed 

 that these" digits were permanently free — not fused as in 

 existing Birds; their distance apart has. of course, been 

 greatly exaggerated in the fignre, for the sake of demonsti'a- 

 tiou. Such a manus is characteristic of the Archornithiform 

 typ)e, which, so far as we know, must always have had the 

 metacarpal and finger-bones separate. [C/'. the characters 

 given by Dr. Gadow (P. Z. S. 189.2, p. 236) for his subclass 

 Arch or nit lies.'] 



The section from the carpus to the humero-radio-iilnar 

 articulation is an artificial severance, introduced in the sketch 

 in order to obtain room to demonstrate the question of the ' 

 feathers in an easier manner, just as the digits II. and III. 

 have been drawn widely apart for the same reason. It must 

 be explained at once that the question of separation of these 

 bones does not enter into the discussion at all. 



The major coverts which come under considei-ation in our 

 argument are coloured red. On the ulna the remiges 

 ranging from the 1st to the 8th are cut off short. 



The position of the carpal remex (belonging to the carpal 

 covert, which has been the subject of our previous comment) 

 is indicated by a cross (x). Its suppression is undoubt- 

 edly analogous to the suppression of the 5th cubital remex, 

 marked by a dagger (f) in fig. 3. We ar^, in fact, better 

 able to understand the apparent anomaly of a flight-feather 

 being suppressed at such an unexpected point when we 

 compare the one instance with the other. 



The process of suppression is going on under our very 

 eyes, as we see in tlie case of the carpal remex, which still 

 exists, though in a dwarfed condition, in the Gulls, and is 

 not vestigial as in other families of birds. There is a reason 

 for this suppression, for the carpal i-emex occurs at a point 

 of the wiug where the existence of the quill of a flight- 

 feather becomes extremelv difficult, owing to the mechanical 



