Vol. XVIII 



IQO 



^^^n C\.x^¥i,PterylosisofPodargusa}idt/ieCaprimulgi. 1 67 



Measurements: Length, 4.85 in.; extent, 8.00; wing, 2.60; tail, 2.45!; 

 tarsus, .62 ; culmen, .30. 



Compared with all available material the new form is clearly 

 recognized at a glance, and with those specimens from northern 

 California, Oregon, and Nevada, having very light underparts 

 shaded with ochraceous, especially so. 



I take pleasure in naming this peculiar bird after my generous 

 friend Colonel John E. Thayer of Lancaster, Mass. 



THE PTERYLOSIS OF PODARGUS : ^YYYl NOTES ON 

 THE PTERYLOGRAPHY OF THE CAPRIMULGI. 



BY HUBERT LYMAN CLARK. 



Through the kindness of Mr. F. A. Lucas of the National 

 Museum, a very fine alcoholic specimen of Fodargus recently 

 came into my hands for the study of its pterylosis. Unfortunately 

 there is no label with it to indicate either the species or the locality. 

 It is not likely, however, that specific variations in the pterylosis 

 of this genus are any greater than among the other Caprimulgi, 

 where they really amount to very little. Nitzsch says that the 

 pterylosis of Fodargus gigas is entirely like that of Caprimulgus^ 

 excepting the dorsal tract, but as his examination was probably of 

 a dried skin, it is not surprising that he overlooked some veiy 

 important differences. As a matter of fact the pterylosis of 

 Fodargus is very distinctive and shows some very interesting and 

 important peculiarities. 



The front part of the head at the base of the upper mandible is 

 densely feathered and this tract continues backward over the 

 crown as a broad median band. On each side of this, just above 

 the eye, is a single very distinct row of contour feathers. The 

 back of the head is very fully feathered and the upper cervical 

 tract is strong, and divides into two forks which extend to the end 

 of the shoulder blades. The dorsal tract is forked for a much 

 greater distance than in any North American goatsucker ; its two 



