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Show 1875.] MR. A. H. GARROD ON CERTAIN PIGEONS. 367 In the Indian Elephant the stylohyal (s h) is a thin bone composed, in the adult male, of a flat portion, 4 inches long, less than 5 inch thick, and very nearly f inch broad, with parallel sides, obtusely truncated at both ends, which are capped with cartilage. In the standing animal the position of this portion of the bone is nearly vertical. Above, it is closely united to the stylo-temporal region of the skull, whilst the lower end gives origin to the digastric muscle. From the middle of the anterior border continues onwards the body of the bone, at an acute angle with the lower portion of the above-described element, downwards and forwards. This is elongately triangular in shape, 6 inches long, f- inch broad at its middle, and tapering to a point in front, where it gives attachment to a hardly specialized stylohyoid ligament and serves for the origin of the stylo-glossus muscle. The interval between the tip of this stylohyal and the lesser cornu (cartilaginous) of the hyoid bone is 5 inches, or a little less than the length of the process itself. As it descends in its downward and forward course, this tapering stylohyal curves slightly on itself, turning a little outwards. The accompanying figure (p. 366) will explain the condition. The descending digastric process, as it may be termed, may be compared to the posteriorly directed process of the stylohyal in the Ungulata. It differs from it, however, in one essential particular, which is that in the latter it does not give origin to the digastric muscle, but only to the stylohyoid; whilst in the Elephant the digastric arises from its lower end only, and the stylohyoid from the angle formed at its junction with the body of the bone. In the Elephant therefore the deficiency of the lateral intermediate elements of the hyoid apparatus permit of a much greater movement of the base of the tongue than in the Ungulata, whose nearly rigid stylohyals, epihyals, and ceratohyals can allow of little more than an antero-posterior movement of the base of the tongue, in part of the circle of which the hyo-cranial attachment is the centre. 3. Notes on two Pigeons, Ianthcenas leucolama and Erythroe-nas pulcher rima. By A . H . G A R K O D , B.A., F.Z.S., Prosector to the Society. [Received April 1, 1875.] Since my communication to the Society " On some Points in the Anatomy of the Columba"*, specimens of two species of this group have died in the Gardens, which deserve a passing note. Ianthcenas leucolama.-The genus to which this bird belongs has been, by different authors, placed sometimes in the Columbine and at others in the Carpophagine section of the family-the number of the rectrices (12, and not 14) having made its position uncertain, as its general appearance tends to that of the Fruit-eaters. * P.Z.S. 1874, p. 249 etseqq. |