44 PTERYLOGRAPHY. 



united with the main stem throughout its whole course. To this may be added the separation 

 of the gular portion of the inferior tract from the pectoral portion by a space, which is found 

 only in these Vultures, and runs round the neck close in front of the furcula. This may be 

 called the jugular space (apt. jugular e). 



1. GYPAETOS larbatus (Plate II, figs. 1 and 2). 



Of this bird I have repeatedly examined skins, and finally two perfectly fresh specimens (an 

 old female and a young male), sent to me from Coire by the chamois-hunter George Gutscher, 

 the skins and skeletons of which now form beautiful preparations in the zoological collection of 

 the University of Halle. I find the following pterylosis : 



In the feathers of the trunk and head the aftershaft is pretty distinct, even in the 

 bristles of the beak and beard, which are true contour-feathers, and are rendered particularly 

 remarkable by the fact that the barbs are almost entirely deficient on the main shaft, whilst the 

 aftershaft, which is very little shorter, bears distinct barbs on its basal half. All the spaces 

 were densely clothed with large down-feathers of a white or yellowish colour, with the exception 

 of the inferior space in the female, in which the down-feathers were wanting on the breast and 

 belly, forming a brood- spot. The contour-feather tracts also have down-feathers among their 

 feathers ; but in the continuous plumage of the head and neck they were almost, if not entirely, 

 deficient. As these down-feathers are discoloured by a yellow dust, which is also perceived 

 as a hoary (hauchartiges] coating upon the contour-feathers of the head and neck, I was led to 

 regard them as powder-down feathers, which, however, they do not appear to be. They certainly 

 do not form true powder-down tracts. 



From the uniform plumage of the head, which extends downwards for about one third of the 

 length of the neck, three processes originate, one of which runs down the back of the neck, as a 

 spinal tract, as far as the shoulders, where it divides into a broad fork. The other two pass, 

 gradually diverging, along the anterior surface of the neck, and embrace its base by the approxi- 

 mation of their pointed extremities ; a circumstance which is characteristic of Gypaetos. The inferior 

 tract consists of two symmetrical widely separated halves, which are very greatly dilated upon the 

 pectoral muscles. Posteriorly, towards the extremity of the sternum, they are again narrowed, 

 and are continued over the belly as mere narrow bands, which converge from the extremity of the 

 pelvis and terminate near tie anus. The lower portion of the spinal tract is united to the above- 

 mentioned fork between the shoulders by two converging rows of single feathers, and is then con- 

 tinued uninterruptedly as a narrow band along the dorsal vertebra, to terminate at the oil-gland. 

 We may also see very distinctly a broad axillary tract separated from the rest of the plumage of 

 the upper arm, but the femoral tract is entirely deficient. On the upper surface the wings have 

 a homogeneous plumage, uniformly distributed over the great wing-membrane; beneath they 

 exhibit two rows of successively larger feathers on the anterior margin of the great wing-membrane, 

 and the rest is a true inferior iciny-space, clothed, however, like all the spaces, with a soft down, 

 and concealed by the contour-feathers of the anterior margin. In this space is situated the 

 musculus extensor metacarpi radlalis ; the other part of the upper arm bears the feathers of the 

 inferior winy-coverts (pteromata), arranged in three rows, which increase considerably in length 

 towards the elbow. The parapterum inferius (Mohring's ala nolJta) is of considerable size, and 



