552 PTEBTLOGEAPBY OF GOATSUCKERS AND OWLS—CLAEK. vol.xvii. 



groups, but it is hoped tliat the preseut article may not ouly serve as 

 an introduction to such a work, but may also arouse more interest in 

 the study of comparative pterylography. 



CAPRIMUL&I. 



In Kitzsch's "System der Pterylographie" there is given a fairly 

 complete account of the pterylosis of Caprimulgus europceus and farther 

 remarks on G. longipennls, forcipatus, and spahtriis, JEgotheles worce 

 hoUandUc, Podargus gigas^ and Nyctornis wthereiis, but apparently the 

 celebrated German had not examined our North American species. 

 Dr. Shufeldt has carefully described the pteryloses of Anirostomns 

 and Ctiordeiles in his memoir on the Macrochires,* and the former is 

 figured. So far as I know these are the only important papers which 

 have yet appeared bearing directly on the pterylography of the group 

 unless we include Steatornis, which has been examined and the ptery. 

 losis figured by Garrod,t although it is not improbable that others may 

 have escaped my search. 



The Caprimulgi are remarkable for the variations shown in the 

 pteryloses of the different genera, but the plan is similar in all the 

 Korth American species and may be briefly summed up as follows: 

 The whole head is fully covered with feathers, which are, however, 

 arranged in more or less complete and often parallel longitudinal rows, 

 forming on the forehead and crown definite patterns, each genus hav- 

 ing its own peculiar arrangement. From the head there extends back- 

 ward dorsally the upper cervical tract which, dividing between the 

 shoulders into two strong forks, extends to the end of the shoulder 

 blades. The dorsal tract, which begins immediately behind this fork, 

 shows great variation in its distinctness and extent, but is usually 

 more or less forked at first and then, uniting into a single tract, runs 

 backward to the rootof the tail. Anteriorly it may unite its two branches 

 with those of tlie cervical tract, thus inclosing a diamond-shaped 

 spinal space, as best shown in Phalcenoptilus, or it may spread out more 

 decidedly toward the sides and even send forward a few feathers almost 

 to the humeral tracts, as is well shown in Chordeiles virginianus. The 

 humeral tracts are strongly defined, and the upi^er surface of the wing- 

 is very completely feathered, except for an evident apteriuni at tlie 

 outer end of the humerus. The f)arapterum is not always very evident, 

 but usually connects the humeral tract with the feathers of the forearm, 

 of which there are seven or eight more or less complete rows, the lower 

 three or four being the secondary coverts, whik^ there are also two very 

 strong rows of primary coverts. Directly at the knee-joint is a i^romi- 

 nent femoral tract, which, after crossing the tibia diagonally, extends 

 part way along the posterior edge of the femur, although it never reaches 

 as far as the dorsal tract. The pterylosis beneath is more uniform. The 



* Jour. Linnean Soc, xx, pp. 299-394. 

 t Proc. Zool. Soc, 1873, p. 526. 



