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Show 1901.] PTERYLOSIS OP THE GIANT HUMMING-BIRD. 315 pterylosis and that of Patagona. The converging lines of feathers that run backwards over the crown, the crescentic row of feathers over the eye, and the crescentic apteria, internal and external to this latter row, are features that the Swift possesses in common with the Humming-bird. But, on the other hand, the absence of the median frontal and occipital apteria, of the eyelashes of the upper lid, and in general the uniform feathering of the back of the head, all these are striking differences. Text-fig. 79. Pterylosis of Collocalia spodiopyga. A, dorsal view; B, ventral view of wing. In Caprimulgus macrurus (text-fig. 80, p. 316) the arrangement of the feathers on the head is as follows : - A double row of feathers starts on the dorsal side of each nostril and curves inwards to approximate to its fellow on a level with the anterior border of the eye, leaving a lanceolate space vacant between, much as in the Humming-bird. A few median feathers intervene between the two rows (each of which has become uniserial) on the top of the head, and behind these the two rows first fuse in the middle line, then diverge slightly (behind the level of the eye), and each afterwards bifurcates prior to running down over the occiput and nape. T w o other rows immediately external to these on each side run |