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Show 468 MR. W. A. FORBES ON L E P T O S O M A DISCOLOR. [June 15, not very divergent, but is dilated terminally, and develops a recurrent hook, which, however, is not very distinct. There is a circlet of feathers round the vent, and a short tract of feathers behind it, on each side of the fleshy part of the tail, continuing the direction of, though quite separate from, the main inferior tract of its side. The feathering of the head above is continuous, and from it the anterior moiety of the dorsal tract runs, being anteriorly continuous at the sides, as already noted, with the inferior tracts, along the dorsal median line of the neck, as a rather broad, thickly feathered band, which forms a strong interscapular fork, just as in Coracias and the Parrots, the ends of the fork lying about \ inch anterior to the posterior extremities of the two scapulse. The posterior moiety has also a forked form, the two arms enclosing a fairly broad naked median space, and only uniting about 1 inch in front of the oil-gland, the united tract so formed ceasing altogether about | inch in front of that organ. This posterior fork is very narrow anteriorly, not more than two feathers wide ; indeed, for the first two or three rows each arm consists of only one feather in each row, and the two arms run in between the forks of the anterior moiety, just as in the Parrots, Coracias, and some other birds. Posteriorly the fork widens, and becomes connected closely with the scattered contour-feathers which are found outside it, over the space between the dorsal tract proper and the lumbar powder-down patches, so that on the rump the dorsal tract appears to consist of five or six rows of feathers on each side of the median line. There is a very strongly feathered and broad band of feathers over the knee, being the anterior end of the lumbar tract of its side ; this tract is quite distinct from all others but the crural, which are much weaker and clothe the leg as far as the "ankle." The powder-down patches, one on each side, lie between the posterior portion of the dorsal tract and the lumbar tracts. They form elongated patches, extending forwards over the femur as far as the sartorius muscle, and backwards to within ^ inch of the vent; their dorsal border is parallel to the dorsal tract, the ventral to the lumbar ones. On the inside of the skin they are conspicuous as dark grey patches, formed by the closely aggregated insertion of the feathers of which they are composed, these lying at a less angle with the skin than the contour-feathers. Nitzsch1 has described the pterylosis in Coracias garrula and C. indica, with figures of that of the former, and in Eurystomus gularis. I have examined the first-named species in the flesh, and also a skin of Atelornis crossleyi. In all essential respects, as will be seen by a comparison of the above description with Nitzsch's figures of Coracias garrula, Leptosoma is essentially Coraciine, though it differs from all others of that group in its possession of powder-down patches2. 1 Pterylogr. (Bay Soc. ed. p. 89). 2 I m a y here mention that Atelornis crossleyi differs as regards its pterylosis but slightly from tiie Coraciine type. It has the same interrupted dorsaftract, each half having a furcate form ; but here the interscapular fork is very short and narrow, and does not enclose the anterior part of the posterior fork, |