OCR Text |
Show 414 MR. A. H. GARROD ON THINOCORUS AND ATTAGIS. [May 1, nestling of Attagis gayi, in spirit, from Chili; and I take the present opportunity of bringing before this Society m y notes on their structure. Of the former of these species Mr. Eyton has fully described the visceral anatomy and the osteology in the ' Zoology of the Voyage of the " Beagle " '1; and in his ' Osteologia Avium '2 will be found an account of the skeleton, together with a figure of the sternum, of the latter. By Mr. Eyton, in his account of Thinocorus, these birds are referred to the order Gallinae ; but in his more recent work they are included with Chionis, to constitute the Chionididse, which are by him placed after the Otidae (comprising the Otinae and Tinaminae), and before the Charadriidse, as families of his order Lit-tores. By Mr. G. R. Gray, in his 'Hand-list of Birds,' they are separated from the Chionididae, between which and the Glareolidse they stand as a division of the Grallee. This is much the same position as that in which they are located by Messrs. Sclater and Salvin in their ' Nomenclator Avium Neotropicalium.' Nitzsch, as Burmeister tells us, was disposed to place them in his group of the Alectorides, along with Chauna, Otis, Cariama, Psophia, and Grus; whilst Wagler placed them with the Pteroclidse; but Burmeister himself is of opinion that "this remarakable bird (Thinocorus rumicivorus), which Wagler very improperly compares with the Sand-Grouse (Pterocles), is in every particular an aberrant Scolopa-cine form, related to Glareola in exactly the same way as Chionis to Heematopus, or Dromas to Recurvirostra"3. As far as pterylography goes, not much of importance with reference to the position of the Thinocorinae can be learnt. In that thev possess a tufted oil-gland they differ from the Pteroclidse and Co-lumbse, in both of which families it is nude. On the whole the pterylosis is typically Limicoline. With reference to the alimentary canal, the tongue is simple and triangular, occupying most of the space between the rami of the mandible. The oesophagus is not large, but develops a capacious and well-defined globose crop, situated just above the furcula. The gizzard is muscular, not large, and it possesses simple triturating pads like those in the majority of non-carnivorous birds. In the specimens of both Thinocorus and Attagis under consideration the intestines are 12*5 inches in length; but it must be remembered that the Attagis is a nestling. The colic caeca in the Thinocorus are 2*25 and 2*5 inches long; in the Attagis they are both 3 inches. Myologically, the ambiens muscle is present, although slender. Both the femoro-caudal and its accessory head exist, of equal breadth. The semitendinosus, together with the accessory semitendinosus are of average size, whilst the semimembranosus is peculiarly slender. The myological formula, therefore, in conformity with the nomenclature adopted in m y paper " O n the Muscular System of Birds," in the Society's 'Proceedings' for 1874 (p. Ill), is A B, X Y. The vastus externus covers the biceps cruris; and in the foot the 1 Part iii. p. 155. 2 P. 177, and plate xxi. fig. 3. 3 Nitzsch's ' Pterylography,' Royal Society's translation, p. 139. |