Oil-bird (Steatornis caripensis) . 83 



six small white finger-marks, situated upon their external 

 borders. The under surface of the tail is altogether lighter- 

 coloured than the upper surface ; but the opposite is the case 

 with the wings. 



The bill is of a rich brown tint. Feet and legs flesh-coloured 

 and without scales or feathering. 



The large round pupil of the eye is dark blue ; the iris, only 

 a narrow ring, in contrast is of a deep brown. 



Weight. — In this specimen the fresh body weighed but six 

 and a half ounces. 



Admeasurements. — Greatest stretch of the wings 32 inches ; 

 tail from root to its free end 6^ inches ; from the tip of the 

 beak to the rump 1 1 inches, the neck being outstretched and 

 the tape passed in a straight line. The head and beak, taken 

 in the median line, by external measurement, are 3 inches, but 

 appeared only 2| inches when using a pair of callipers. Beak 

 barely 1^ inch long. 



Pterylosis. — Rectrices ten ; primaries ten ; secondaries 

 eleven or twelve. The third and fourth primaries are the 

 longest, the remainder graduated. Tail fan-shaped. Oil- 

 gland large, bare, and possessing a long, filiform, featherless 

 nipple. All the feathers throughout the body, and more no- 

 tably those of the tail and wing, are acuminate. There are no 

 powder-down patches. Very many light downy feathers, 

 however, are present — some parts, for example the external 

 aspect of the thighs, being almost destitute of other longer 

 feathers. 



Legs and feet. — The legs are completely devoid of feather- 

 ing and of scales, the only cuticular appendage being a few 

 downy hairs, which are situated near the feet and chiefly 

 above the posterior toe. The skin hangs loosely, the flesh 

 shining through and producing their pale and characteristic 

 colour. 



Length of tibia l - 8 inch, of the tarsus 1 inch. The three 

 anterior digits are subequal in length, the middle one dis- 

 playing a slight advantage. Length of the middle digit minus 

 the claw 1 inch, the nail increasing it by 04 inch. The di- 

 rection of the front toes is nearly straight forwards and pa- 



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