ME. E. DEGEN ON ECDTSIS. 355 



both the metacarpo-digital and the cubital portions of the wing. The column of 

 cyphers to the right contains the sums total of the amount of all the flight-feathers 

 under moult in each specimen. The cyphers placed at the bottom of the columns are 

 the sums total obtained for each remex itself, their aggregates agreeing with the grand 

 total of the other column in the right-hand corner. 



The cyphers on the second line at the bottom show the number of specimens 

 observed for the moult of that particular remex, and beneath these, in opposition to 

 the numerical order of figures of the remiges at the top, are placed the letters referring 

 to the successive phases (c/. also diagrams on Plates XXXVI.-XXXVIII.), in alpha- 

 betical order, for the remiges of the hand portion. Their corresponding equivalents 

 for the order of the cubitals are designated by dashes, thus : ' " '". 



The symbol O signifies that the remex has been shed, and the dotted spaces are the 

 places still occupied by the old quills. 



As already mentioned, a Table has also been provided for the percentages of 

 reduction of power of flight, giving the amount in each specimen, and for each portion 

 of the wing separately, the totals for each wing, and the grand totals for both sides. 



V. — Definition of the " Moult." 



A. On " Adventitious Plumage." 

 Before a bird assumes the deciduous plumage which is annually replaced in the 

 same manner, viz., by the process known as the " perennial moult," it is provisionally 

 clothed with generally one, though often two liveries, differing both in function and 

 growth. They require careful consideration on account of their genetic importance. 

 The successive liveries are : — 



1. An adventitious downy investment of the nestling, or " Embryo-Plumage." 



2. A non-deciduous (ontogenetic) garb of the fledghng, or "Annual Plumage." 



3. A deciduous (phylogenetic) featherings- of the mature bird, or "Perennial 



Plumage." 



It is to the second livery that usually the term " embryo-plumage " is given, chiefly 

 because it produces the first set of quills and contour-feathers {Teleoptiles). 

 - In the nestling of dasyimdic birds a downy covering {JSfeossoptiles) of the body 

 precedes the latter or plumage of the fledgling. The term " embryo-plumage" there- 

 fore belongs to this downy adventitious covering: cf. Wittmer Stone (44), pp. 115-117, 

 "Number and Times of Moult"; also Patio (19), p. 258. These down-feathers 

 are the forerunners of the true contour- and covert-feathers, whose places the latter 

 afterwards occupy. They must therefore not be confounded with the downy structures 

 which grow in the interstices between the latter, such as are found in Ducks, Swans, &c. 



VOL. XVI. — pakt viii. No. 2. — Mai/, 1903. 3 e 



