| OCR Text |
Show 1905.J DOLPHIN'S FROM TRAVANCORE. 125 the forehead, the inner enclosing a pale lappet-shaped zone which includes the narial aperture, and the outer becoming obsolete halfway up. Eyes dark reddish brown. Lower jaw lighter than upper. Lips dull whitish. Fins falcate. Length of skull 16*3 inches; breadth 7-6 inches. Symphysis much shorter than one-fourth total length of mandible 27 27 Teeth and ^ = 54 and 53. Simple, conical, and pointed, more or less compressed towards the r o o t; antero-posterior diameter 6-5 mm. Two teeth in the premaxillae, and the first two mandibular ones, which were concealed in the gum, much smaller (diameter 2 mm.). In spite of its being a somewhat immature specimen apparently referable to the genus Tursiops, which it resembles in many respects, the pterygoids are widely separated in the middle line, with the posterior border divergent. Vertebrae: C. 7, D. 13, L. 15, Ca. 25 = 60. The atlas and axis only fused together. Ribs 13, the first four two-headed. Other characters as in T. fergusoni. From the general characters of the specimen, the number and size of the teeth, the vertebral formula, and the relative shortness of the mandibular symphysis, I cannot but conclude that its reference to Tursiops is correct. It is true that in the divergence of the pterygoids it differs from the typical T. tursio', but since the same feature occurs in the specimen identified with T. catalania, this affords no grounds for generic separation. In the following table are given the dental and vertebral formulae of the Dolphins assigned to the genus Tursiops, inclusive of the present specimens :- 1. Tursiops tursio (Fabricius). Teeth ^ = 44. Vertebrae: C. 7, D. 13, L. 17, Ca. 27 = 64. Pterygoids in contact. 2. Tursiops abusalam (Riippell). Teeth ^ = 52. Vertebrae: C. 7, D. 12, L. 16, Ca. 26 = 61. Pterygoids (?) in contact. 3. Tursiops sp. (Trevandrum, 1904.) Teeth ~ and = 54 and 53. Vertebrae : C. 7, D. 13, L. 15, Ca. 25 - 60. Pterygoids divergent. |
