. Text book of zoology. Zoology. Class 5. Aves. 433. longest feathers on tlie body.; as a rule, they have no aftershafts, and the down-like proximal portion is very small, or is absent; they lie in very deep feather-follicles, the remiges in a row along the outer edge of the fore-arm and hand, the rectrices on the tail. In tte extinct Archmopteryx, tlie rectrices were arranged in two longi- tudinal rows, one on either side of the long tail. In some existing Birds also, they occur in two distinct oblique rows on the much shoi-tened tail; in others, this part is so very short that the longitudin
. Text book of zoology. Zoology. Class 5. Aves. 433. longest feathers on tlie body.; as a rule, they have no aftershafts, and the down-like proximal portion is very small, or is absent; they lie in very deep feather-follicles, the remiges in a row along the outer edge of the fore-arm and hand, the rectrices on the tail. In tte extinct Archmopteryx, tlie rectrices were arranged in two longi- tudinal rows, one on either side of the long tail. In some existing Birds also, they occur in two distinct oblique rows on the much shoi-tened tail; in others, this part is so very short that the longitudinal series foi-m a cui-ved ^ B transverse row. The down feathers [flumce), which are generally completely covered by the contour feathers, differ from them, in that the whole vexillum is similar to the proximal portion in the latter; they consist of soft barbs, which are often very long and beset with long barbules without hooks, the shaft is thin and feeble, often even quite rudimentary, so that the barbs arise close together at the distal end of the quill. There is often an aftershaft on the down feathers ; not infrequently it is almost as large as the main shaft. The down feathers are usually whitish or grey, whilst the contour feathers vary much in colour. The two types described pass gradually into each other; there are plumse which, in virtue of their strong shafts, etc., approach the pennse, and modified pennse which are so loose and soft, or which possess so small a portion with hooks, that they form a transition to the plumse. A special form of pluma is the so-called filoplume, a delicate feather with long thin shaft, in which the barbs are few in number, and at the tip of the shaft only; they occur in almost all Birds, arising close to the contour feathers. Among pecuUarly developed feathers, the following may be mentioned: ospreys, which grow on certain parts of the head in many Birds and have no barbs, or only a, few, at the base of the shaft; the pennsB, in the R a
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