OCR Text |
Show 418 MR. A. H. GARROD ON THE ANATOMY OF COLIUS. [May 2, Dr. Murie; the crenulation, however, of the lateral margins of the keel-bearing middle xiphoid process is not apparent. The bone resembles that of the Capitonidae more than the sternum of any other bird (see, for comparison, Eyton's ' Osteologia Avium,' plate 8). In the structure of its soft parts Colius presents several interesting features which assist in the determination of its affinities. The skin is particularly tough, much like that of the Swifts in this respect. Only one carotid artery is present, the left. In the Musophagidae, Cuculidae, Coraciidae, Galbulidae, and Alcedinidae we know that both a right and a left artery are always developed *; whilst in the Bucerotidae Toccus possesses only the left, Buceros having both,-the left only being found, as in Colius, in the Picidae (i. e. Picinae, Ramphastinae, and Capitoninae), Upupidse, Meropidae, Trogonidae, and Passeres. As far, therefore, as the carotid arteries are concerned, the Colies do not resemble the Musophagidae, their supposed nearest allies. The comparison with Parrots must be reserved till further on. Myologically, Colius wants the ambitus muscle. It is therefore Anomalogonatous f, and agrees with the passeriform and piciform birds only, differing essentially from the Musophagidae. The femoro-caudal is well developed, but has no accessory head. The semitendinosus and its accessory head are both fairly developed. The myological formula of the bird on the system adopted by me in my paper on Classification, just referred to, is A,XY, the same as that of most passeriformes and piciformes, but differing importantly from that of the Musophagidae (AB,XY) in the absence of B, the accessory femoro-caudal muscle. The tensor fascia of the thigh does not in the least cover the biceps muscle. In the arrangement of its plantar tendons Colius, although so peculiar and uncertain in the manner in which it employs its toes, exactly resembles the feeble-footed Alcedinidae, and hardly differs from the Coraciidae, Meropidae, Bucerotidae, and Caprimulgidae. In Musophaga the distribution of the tendons is on quite another principle, as it is in the Psittaci;};. The intestines of Colius are voluminous and short, being only 9 inches in length. I could find no trace of intestinal caeca. Nitzsch has shown that the oil-gland is tufted, and that there are ten rectrices. In m y paper on the classification of birds I proposed to distribute the Anomalogonatae into two groups, according to whether the caeca are present and at the same time the oil-gland is nude, or the caeca are absent and the oil-gland is tufted, arranging them in the following manner : - * P. Z. S. 1873, p. 464. t P. Z. S. 1874, p. 116. t Vide P. Z. S. 1875, p. 339. |