Families BUBONIDAE AND STRIGIDAE. 

 (Plates 95—99). 



The distinguishing feature of the texture of the shell of all the 

 species of these Families is the fine, uniform lime-granulation *) 

 which — particularly in the case of the genera Athene, Asio and 

 Syrnium — is often accompanied by the presence of small promi- 

 nences (in my opinion: local accumulations of lime concrements), 

 of which larger ones are frequently found close together near the 

 ends of the eggs, and which sometimes also occur in the shape of 

 lines. It is a fact, however, that eggs of many other species of birds 

 also exhibit these prominences. Longitudinal or latitudinal grooves, 

 in which a large number of pores usually occur close together, are 

 mentioned by Rey, solely in the case of aluco, as frequently occur- 

 ring; they are, however, also found on eggs of other species, although 

 sometimes in a less pronounced fashion than on those of aluco. 

 In no case can they obtain as a characteristic proper exclusively 

 to aluco. 



The eggs, Strix excepted, are of a more or less spherical shape, and 

 in the case of Athene and Syrnium they are even distinctly spherical. 



; ) For the purpose of examining the texture of eggshells I recommend that 

 they should be magnified 16 times. In this connection it should be borne in 

 mind that in general the granulation of eggshells is less uniform at the pointed 

 end and consequently seems coarser there than elsewhere. 



