MOEPHOLOGY OF THE OWLS. 



257 



occur in pairs (fig. 3, G) at the proximal nodes ; beyond this thej^ suddenly disappear, but 

 the corresponding" region is marked by a gentle swelling containing a dark pigment, 

 which in masses appears black. 



The adult down-feathers of Asio, Speotyto, and otlier Owls closely resemble those of 

 the Kestrel {Falco t'mmmculm, fig. 3, E) ; but they may be distinguished by the 

 following points : — In the latter the nodal areas of tlie radii are more numerous, the 



Fig. 3. 



B 



--^rr/^^- 1.. -'W- - J»iTf??r?r?? 



^^^ ^^m^ ^^^ — -— 



A, portion of a rndius from a defini- 

 tive down -feather of Capri- 

 multjus eurupa'us. The swelling 

 of the nodes is somewhat ex- 

 aggerated in the figure. B, por- 

 tion of a radius of a pre-peniia 

 of C. e.uropcms. C, portion of 

 a radius from a pre-plumula of 

 Falco tiiinunculus. D, portion 

 of a radius from a pre-penna, 

 and E, portion of a radius from 

 a definitive plumule of F. tin- 

 nuncxlus. F, portion of a radius 

 from a pre-penna, and G, por- 

 tion of a radius from a definitive 

 plumule of Spxotyto cunicularia. 

 f, filum. 



,/ 



rhachis is much longer, and there is a vestigial aftershaft. They may be very readily 

 distinguished from those of Caprimulrjus (fig. 3, A) by the greater length of the radii in 

 the latter, the long black nodes — longer than the internodes and very little thicker, — and 

 the absence of fila. Like the Kestrel, the down-feathers of Caprimulgus possess a long 

 rhachis and a vestigial aftershaft. 



Filophmies. — In the adult these present no special features of interest. The rhachis 

 is long, bearing from two to three rami (fig. 4). The radii are of moderate length, 

 and bear, here and there, a few fila. The only case in which I failed to find filoplumes 

 in the adtdt was that of Speotyto cunicularia. 



35* 



