8TBIGES: NOCTURNAL BIRDS OF PRJ^Y. 



499 



These are tufts of lengthened feathers rising over the eyes from the forehead, and commonly 

 called "oar-tufts"; but they have nothing to do with the ears, and are more appropriately 

 named '' plumicorns," or feather-horns. More reliable characters may be drawn from the 

 structure of the external ear and facial disc, the modifications of which appear to bear directly 

 upon mode of life ; these parts being as a rule most highly developed in the more nocturnal 

 species ; some points of internal structure have been found con-espondent. Thus, one group, 

 of which the barn owl, Aluco flammeus, is the type, is very dit^tinct in the angular contour and 



Fig 349 — " Est illis Stngihus nomen sed noniiius hujus 



Causa quod liorrenda stridere iiocte solent." — UviD, Fasti, vi. 139. 



" Screech-ov'ls thev 're called, because with dismal cry 

 In darkling night from place to place they fly." 



high development of the facial disc, pectination of the middle claw, and other characters upon 

 which a family AluconidcE may be established. Probably the rest of the suborder fall in two 

 subdivisions of a single family Strigidce, the essential characters of which have already been 

 contrasted with those of A luconidcc. 



The nearest relatives of the Siriges, outside their own order, are the Caprimulgi — the 

 relationship being really very close through the genus Steatornis. As is well known, owls are 

 eminently nocturnal birds ; but to this rule there are numerous striking excei)tions- This 

 general habit is correspondent to the modification of the eyes, the size and structure of which 



