MYOLOGY OF OPISTHOCOMUS CRISTATUS. 367 



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 was a 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 (PI. LXIII. fig. 3), the 

 ingluvies or crop was preserved. The oesophagus 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 oesophagus, 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 restraiaing barrier to the undue disten- 

 tion of the crop. 



The outer layer of muscular fibres of the oesophagus 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 lowest segment being much 

 stronger, firmer, and more numerous. j ■ - 



Immediately beneath the circular fibres of the gullet is a lay^- 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 



