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Show 344 MR. R. S. WRAY ON THE MORPHOLOGY [Apr. 5, at present, and has this advantage that it is applicable to both sides of the wing, and reduces the terms used to a minimum. Professor Flower and Dr. Sclater have done me the kindness of revising the nomenclature1 for the remiges. The term " tertials " or "tertiaries" has been abandoned, " cubitals " always including them when present, because there is no way of absolutely distinguishing any definite number of remiges as belonging to this special category. There is certainly a distinction to be founded upon the arrangement of the little muscular slips and tendons attached to the cubital remiges ; but it would not be of much use in practice, owing to the difficulties in the way of determining it with regard to many birds. The main points of interest brought to light by the examination of a considerable number of birds, some of almost every large group, will be treated of, the wing of the Wild Duck, which is an extremely good type, being first described in detail. The preparations in the Natural-History Museum fully illustrate this paper, and most of the accompanying drawings are taken from these preparations or from essentially similar ones. The Wild-Duck's Wing. When the wing is extended for flight, the surfaces and borders correspond to those of the primitive vertebrate limb, the preaxial border being directed forwards, the postaxial backwards, and the dorsal.and ventral surfaces upwards and downwards respectively. It is in this position the wing is best studied ; and when plucked of feathers posteriorly it presents a fold of skin from the elbow to the tip in which the flight-feathers and their principal coverts are embedded ; these and their position are first described. When the wing is prepared as shown in the drawing (Plate XXIX.) two main groups of quill-feathers are seen :-the S E C O N D A R I E S or C U B I T A L S attached to the ulna, and the P R I M A R I E S or M E T A C A R P O - DIGITALS attached to the manus. Of the latter, six, the Metacarpals (1-6), are attached to the metacarpus, and five, the Digitals (7-11), attached one (addigital, 7) to phalanx 1 of digit in., two (middigitals, 8, 9) to phalanx 1 of digit n., and two (predigitals, 10, 11) to phalanx 2 of digit n. The distal predigital (11) is always small, and is designated the remicle; its relations, described in detail later, show that it is as much a primary as the so-called " spurious tenth " of many Passerines. The quill-feathers on the cubitus stand out more or less at a right angle to the bone; those on the manus form a gradually increasing obtuse angle, till the last feather lies parallel with the phalanx to which it is attached. The remiges are best numbered from the wrist-joint, proximally for the cubitals and distally for the metacarpo-digitals ; because with scarcely any exception reduction in number takes place at the distal end of the manus and the proximal end cf the cubitus. 1 A somewhat similar nomenclature was proposed by Dr. Alix, ' Journal de la Society philomatique,' 1874, p. 10. "Sur les plumes ou remiges des ailes des oiseaux." |