MR. E. DEGEiN" ON ECDYSIS. 389 



2. Inferior es. 



Metacarpo-di gital Portion. — The feathers which constitute this series of minors are 

 of such abortive growth that they are practically of no value for the covering of this 

 part, and, as a consequence, no information is available with regard to the order of 

 their renewal. 



Cubital Portion. — The feathers of this row, not so much on account of their 

 diminutive size (being scarcely f the length of the medians), but because of the 

 method of their renewal, are well worthy of a more special consideration. 



It would seem that, with the suppression of the major coverts on the underside of 

 the wing in the Passeres, the physiological functions of the latter had been transferred 

 to the next row, viz. the medians, and in the same way that of the medians to the 

 minors. Both these series have their moult more accentuated and more in keeping 

 with that of the higher equivalents of the dorsal surface. 



The first appearance of the members of this co-series is somewhat earlier than that 

 of their dorsal congeners in the very young bird. In Nos. 7, 8, and 9, for instance, 

 all very young individuals and of early dates, this row moults in advance of the dorsal 

 one. Singularly enough, in the three specimens mentioned, the renewal begins at the 

 carpal flexion, and proceeds inwards, which is in an opposite direction to the renewal 

 of the dorsal series. This fact therefore foreshadows the ultimate method of moulting 

 in groups, and is significant. 



Specimens 5, 11, and 12 are examples of the earliest, or caducous, mode, in which 

 the inferior row is developed strictly in synchrony with the members of the dorsal row. 

 No. 12 makes an exception, perhaps, so far that the coverts of the inferior row are 

 all in a nascent state only, and they are consequently in arrear of those of the dorsal 

 row, whose components have developed f of their ultimate length, and symmetrically 

 from the two wings. 



The transition from the iwemature to the fully mature condition of moult is a very 

 erratic one for the whole series. In the few specimens, however, which show such 

 evidence of transition, as, for instance, Nos. 13 (both sides), 15 (right side only), and 

 16 (left side), group-moulting sets in first, sometimes for the proximal, sometimes for 

 the distal group, and in one case contemporaneously for both these groups; whilst the 

 middle group, consisting of coverts 7, 6, and 5, does not appear to be affected until 

 much later. 



In anv case, asymmetry seems to be a conspicuous feature in the replacement of 

 this set for the individuals undergoing transition from the juvenile to the mature 

 conditions of the moult. The coverts of this, as well as those of the dorsal series of 

 minors which are allied to the remiges of group III., namely 7-5 — the last to change 

 in every case, — moult in advance of the latter. This is well seen in all the specimens 



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