620 



5 YS TEMA TIC S Y NOP SIS. — RA P TOR ES — S TRIGES. 



group. They are highly monomorphic, without extremes of aberrant form ; Lut the ease with 

 which they are collectively defined is a measure of the difficulty of their rigid subdivision, which 

 is not yet satisfactorily determined. Too much stress has been laid upon the trivial, although 

 evident, circumstance of presence or absence of the peculiar "horns'' that many species pos- 

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

 called "ear-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 correspondent. Thus, one group, 



Fig. 4 .'5. — '■ Est illis Slririihu!: nomen ; sed nominis Imjus 



Causa quod horrenda stridere uocte soieiit." — Ovid, Fiisli, vi. 139. 

 " Screec/i-oivls they 're called, because with dismal cry 

 lu darkling uight from place to place they fly." 



of which the Barn Owl, Aluco flammeuSi is type, is very distinct in the angular contour and 

 high development of the facial disc, pectination of 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 lueonidtc. 



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

 being really very close through tlie genus Steatornis. As is well known. Owls are eminently 

 nocturnal birds ; but to tliis rule there are numerous striking exceptions. This general habit 

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

 birds to see by night, and cause them to sufi"er from the glare of sunlight. Most species pass 

 the daytime secreted in hollow trees, or dense foliage and other dusky retreats, resuming their 



