MYOLOGY OF OPISTHOCOMUS CRISTATUS. 567 
There is a massive sort of grandeur about the digits of this bird, the more interesting 
when comparison is made between the size and weight of the bird and the degree of 
development of the feet. 
In many respects there is a wonderful analogy between the myology of the common 
Barn-owl (Strix flammea) and the Opisthocomus. 
In some minor respects the analogy seems to depart from the Barn-Owl, and coincide 
with that of the common Wood-pigeon. 
Judging from its general anatomy, I should infer that it wasa bird that did very little 
flying, but rather spent the greater part of its time on the ground. Although there is 
no evident lack of power in the alar muscles (rather the contrary), the shortness of the 
limb and the absence of the elastic membrane, contrasted with the powerful development 
of the crural muscles, favour the supposition that the habits of the bird are more 
pedestrian than volant. 
Both specimens had been eviscerated; therefore I cannot give any account of the 
viscera. Fortunately this has already been done by abler pens than mine. 
As I have mentioned, and as can be seen by the diagram (Pl. LXIII. fig. 3), the 
ingluvies or crop was preserved. ‘The cesophagus leading to it is large and wide, much 
more so than I should have anticipated from the nature of the food found in the crop. 
Immediately prior to its termination in the crop it undergoes enlargement or dilata- 
tion. A constriction rapidly succeeds, followed by the primary dilatation which con- 
stitutes the upper cavity of the crop, bending and directed towards the left side. It 
then recurvates to the right side, its extremity being directed upwards and inwards, 
terminating in a canal of about the same calibre as the cesophagus, which passes 
vertically downwards, being closely applied against the dorsal aspect of the crop in the 
median line. Broadly speaking, the crop may be said to consist of two portions bent in 
a horse-shoe fashion upon one another, the lower segment being the greater and stronger. 
Applied over the crop is a strong membrane, in which are muscular fibres apparent to 
the unaided eye. This membrane is continuous upwards with the deep layer of cervical 
fascia. If it has any function, it would be as a restraining barrier to the undue disten- 
tion of the crop. 
The outer layer of muscular fibres of the cesophagus is circular; and these, as they 
approach the crop, become oblique and finally vertical in direction, although circularly 
disposed round each segment of the crop, those of the cones segment being much 
stronger, firmer, and more numerous. J 
Immediately beneath the circular fibres of the gullet is a layéh of longitudinal fibres. 
These are lost in the first segment of the crop; at all events I could not find a trace of 
them in the second and lower segment. This arrangement of the muscular fibres is 
diametrically opposite to that which prevails in the higher animals. 
On opening the crops of both specimens I found them distended with semipultaceous 
masses of vegetable food, consisting of numerous coriaceous envelopes of a sort of bean 
