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Show 1880.] MR. W. A. FORBES ON LEPTOSOMA DISCOLOR. 4Q9 In the Cuculidse the dorsal tract, though it divides between the shoulders, is perfectly continuous throughout, enclosing an elongated oval space (vide Nitzsch's figures of Cuculus canorus and Centropus rufipennis I.e. pl. iv. figs. 12 & 14). In the Cuculid* too, as is well known, the aftershaft is absent and there are but 10 rectrices. I may remark that in the possession of an ^erscapular dorsal fork the Coracndae and Leptosoma form an exception to Prof. Garrod's generalization1 that when "the dorsal tract develops a fork between the shoulder-blades a bird is homalogonatous." Visceral Anatomy.--The mucous membrane of the palate and mouth is smooth throughout, except along the margins of the nasal aperture, where it develops three or four small blunt retroverted tubercle-like papillae on each side, and also external to this on each side along a line parallel to the axis of the palatine bones, where there is a similar short row of small papillse. _ The tongue is tapering and elongated in shape; its length is 1| inch. The basal part, which alone is fleshy, and supported by the hyoid bones, is of a triangularly sagittate shape, about \ inch long, and provided at its postero-external angles with a few minute, blunt, retroverted papillae; it is prolonged forwards into a horny lamina, which is strongly concave above and forms the greater part of the tongue ; at its apex the part, which is of a slightly tapering shape, is apparently entire2. This tongue closely resembles that of Coracias, and differs from that of such of the Cuculidae as I have examined in wanting the well-developed retroverted spines that are always present on the posterior part of the lateral margins in those birds3. The oesophagus is capacious at first, but rapidly narrows; it develops no crop. The proventriculus is zonary, being | inch deep. The stomach is globose and not strongly muscular ; there is a distinct pyloric bulb indicated externally at the commencement of the duodenum. Internally it is lined with rather soft epithelium, which is concentrically striated. In the present example the stomach contained hairs, apparently of lepidopterous larvee, and the horny jaws and other hard parts of insects ; many of the smaller hairs had become impacted in the soft lining of the stomach, so that this at first sight appeared to be villous. The same appearance has often been described in our common Cuckoo4. The intestines in all measure 12| inches, of which 2f are " large ; " they are not markedly capacious. The caeca5 are long and cylindri-which has a long stem or " handle." There are the same strong lumbar tracts. Below, the outer pectoral tract, given off on the middle of the breast, is only indicated by an enlargement of the main tract, and is not at all free. There are no traces of powder-clown patches. 1 P.Z. S. 1878, p. 931. 2 The tongue of Leptosoma has been figured by M r . Sclater (I. c. p. 688), and also by M . A. Milne-Edwards (I. s. c. pl. 88. fig. 1). 3 Vide also the figures of the tongues of Coua gigas (pl. 63. fig. 1) and C. olivaceiceps (pl. 64. figs. 1, 2) in Grandidier's work. 4 Cf. Hunter's Essays and Observations, ii. p. 285 &c. 5 Figured, with other parts of the intestinal canal, by M . Milne-Edwards, I. c. pl. 88. 1 31* |