No. I.] THE CRANIUM IN THE OWLS. 135 



The nostrils are of medium size, situated low down com- 

 paratively ; their height is 3 mm. and very little more than 

 their width, which is 2 mm. A tuberous cere is situated above 

 the nostrils. 



The cranium, which is quite symmetrical, attains its greatest 

 height posterior to the orbits. 



The beak is short and very much curved ; the mandibles, 

 not taking into account their horny sheath, measured from the 

 frontal bones, will enter 2.6 times into the total length of the 

 cranium. The superior surface of the craniwtn is even and 

 smooth, without any median furrow, a character which, among 

 the North-European species, it possesses in common with Glau- 

 cidium passerimtm} 



The supraorbital process is, in the older individuals, espe- 

 cially long, and is seen to be a narrow, stiletto-formed, osseous 

 process, that is directed obliquely backwards. 



The forehead, posterior to the supraorbital processes, is 

 broad, of the same breadth as is that region in front of those 

 apophyses ; that is to say, the frontal borders are very nearly 

 parallel. 



Frontal bones are sharp where they go to form the poste- 

 rior periphery of either orbit. The interorbital septum has 

 its thinner, semitransparent part especially extensive ; in the 

 middle of the alisphenoid there is a vacuity caused by non-" 

 ossification 2 that in size about equals \\\.q. foramen opticiim. 

 The osseous crest of the os squatnosum is completely free 

 superiorly and juts out sharply from the cranium. It is broad- 

 est in the middle, where it develops an apophysis, directed 

 forwards, that conceals the posterior extremity of the quad- 

 rate, when the cranium is viewed upon its lateral aspect. 

 Regarding the cranium anteriorly, the osseous crests are seen 

 in plain view standing out beyond the orbital wings (that is, 

 the osseous crests of the alisphenoids). 



1 While making this translation I have before me three skulls of adult 

 specimens of Surnia ulula caparoch, and three skulls of adult specimens of 

 Micropallas whitneyi. The median furrow is entirely absent in the former, but 

 there is a slight indication of one in the skulls of Micropallas. — R. W. S. 



2 This is referred to in the following words, viz. : " et hudagtigt parti," which, 

 being literally translated, means " a membraneous part." — R. W. S. 



