80 RAPTORES. STRIGIDJ2. 



longer existing) to fill up the chasm which at present sepa- 

 rates the nearest resembling members of the two families, 

 and which appear to be some species of the genus Circus 

 among the Falconidse, and the Accipitrinae or Hawk Owls 

 among the Strigidae. By their near affinity also to the Ca- 

 primulgidce (Goatsuckers), particularly seen in the genus 

 Podargus, the connection between the Insessorial and Rapa- 

 cious birds is beautifully sustained, though a similar de- 

 ficiency of intermediate forms is even in this case observable. 

 By far the greatest proportion of the Strigidoe are noctur- 

 nal or crepuscular feeders, sallying forth from their concealed 

 retreats towards the close of day, when other birds are re- 

 tiring to roost, but when the other animals which form their 

 principal support are quitting their holes to feed, in expect- 

 ed security, during the silence and darkness of the approach- 

 ing night. Some of the species, however, are capable of 

 bearing the light of day ; and these pursue their prey in the 

 same manner as the Falconida. A nearer approach to that 

 family is also here observable, in the smaller size of the fa- 

 cial disk, the dimensions of the eye, and the comparative 

 length, as well as stronger structure, of the wings and tail. 

 In the nocturnal species, which steal upon their prey by the 

 noiselessness of their flight, the plumage is remarkably soft 

 and downy ; the margins of the wing-feathers (the great Or- 

 gans of motion) being loose, and divided into fine filaments, 

 thus offering the least possible opposition in passing through 

 the air, and their progress is by a slow and gentle motion of 

 the pinions. The ear also is of a singular construction, and 

 developed to an extent seen in no other birds, giving them 

 an acuteness and delicacy of hearing, that can detect even 

 the slightest rustling of their prey. Their eyes also, in the 

 greater part directed forwards, are, from their size, position, 

 and construction, beautifully calculated for collecting and 

 concentrating the horizontal and dim rays of twilight. The 

 small degree of attention that has hitherto been given to the 

 peculiar features that distinguish the Owls, especially to the 



