THE ANATOMY OF COLIUS. 351 
the Alcedinids, because in them there is a demonstrable *nterval 
between the free posterior ends of these plates, the intermediate 
septal bond but incompletely uniting them. <A slightly more extensive 
ossification in this region would reproduce a Parrot’s palate in that 
of the Coly. 
Next, with reference to the vomer, the result of carefully watching 
the skull during maceration, and of a minute inspection of the palate 
in the prepared specimen, convinces me that that bone is not ossified. 
In thus lacking the vomer, Colius and Alcedo agree. 
The sternum of my specimen closely resembles that figured by 
Dr. Murie; the crenulation, however, of the lateral margins of the Page 419. 
keel-bearing middle xiphoid process is not apparent. The bone 
resembles that of the Capitonide 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 
Musophagide, Cuculide, Coraciide, Galbulide, and Alcedinide we 
know that both a right and a left artery are always developed ;* 
whilst in the Bucerotids Toceus possesses only the left, Buceros 
having both,—the left only being found, as in Colius, in the Picide 
(i.e. Picine, Ramphastine, and Capitonine), Upupide, Meropide, 
Trogonide, and Passeres. As far, therefore, as the carotid arteries 
are concerned, the Colies do not resemble the Musophagide, their 
supposed nearest allies. Their comparison with Parrots must be 
reserved till further on. 
Myologically, Colius wants the ambiens muscle. It is therefore 
Anomalogonatous,t and agrees with the passeriform and piciform 
birds only, differing essentially from the Musophagide. The femoro- 
caudal is well developed, but has no accessory head. The semi- 
tendinosus 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 Musophagide (AB,XY) in the absence of B, the accessory 
JSemoro-caudal muscle. The tensor fascie 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 Alcedinide, and hardly differs 
* “ Proceedings of the Zoological Society,” 1873, p. 464. (Supra, p. 168.) 
+ “ Proceedings of the Zoological Society,’ 1874, p. 116. (Supra, p. 213.) 
