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Show 1888.] DR. H. GADOW ON THE REMIGES OF BIRDS. 665 PART II. A few Remarks on the Phylogenetic Development of the Remiyes. Mr. Wray has shown that the one or two rows of greater under wing-coverts, Sundevall's " tectrices aversae," were originally situated on the dorsal side of the wing, like the remiges themselves, and that the two hinder series of feathers gradually, during the growth of the embryo, are pushed into the ventral side of the wing. This is probably due to the greater development of the remiges proper, and to the formation of the fascia tendinea, which connects the basal portions of all the remiges with each other. Since this interesting discovery has been made, it is easier to understand the relations between the remiges and greater under wing-coverts in the Ratitae and Spheniscidae, and moreover to arrive at a possible explanation of the phylogenesis of the remiges from a general point of view. Struthio possesses 20-23 cubital and 16 metacarpo-digital remiges. Of the primaries, 8 are carried by the metacarpal bones, one by the remnant of the third finger, 4 by the first, and 3 by the second phalanx of the second finger. There is only one series or row of greater under wing-coverts. Rhea has only 12 primaries, like certain Carinate birds. The total absence of greater under wing-coverts is probably due to their degeneration. Spheniscidae.-Fiirbringer draws attention to the fact that in the Spheniscidae there are more than 30 rows of little scale-like feathers on the dorsal and on the ventral aspect of the wing, i. e. a greater number of rows than there are present in any other bird, even all the median, lesser and marginal coverts included. The largest of these feathers are not, like in other birds, the most ulnar series, but the last but one series on the hand, and the second and third last dorsal rows of the forearm. Each of these rows contains 25-27 feathers on the arm, and 35-36 on the hand. Fiirbringer rightly hints at two possible explanations of this exceptional condition. Either that the Spheniscidae have lost all their true primaries, which they possibly originally possessed, and that this row of 36 feathers does not represent primaries at all; or perhaps that only every third feather represents a primary, although now degenerated, whilst the other 24 feathers are modified down-feathers. However, neither of these two assumptions is supported by facts. That the number of feathers in one row amounts to 36, i. e. three times the number of primaries of certain other Carinate birds, is most probably an accidental coincidence ; otherwise one might assume that of every three feathers of the Penguins, one had become a primary and the other two had been transformed into tectrices aversae. I find that in a large specimen of Aptenodytes pennanti there are no tectrices aversae, all the feathers of the ventral aspect of the wing looking ventralwards with their convex surfaces. This circumstance suggests the assumption that in the Penguins no rows of |