pBKRHOLSER : GRANDAUDAE 405 



inclined on crystals turned so that axis b is more or less vertical, 

 and reaches a maximum of 5 ° ^ 1°. The double refraction is 

 excessively strong, so that no color effects are obtained. The 

 sign of elongation is negative. 



In convergent polarized light: Traces of biaxial figures are 

 sometimes seen, but little can be determined about them. The 

 plane of the optic axes runs lengthwise; the sign is clearly nega- 

 tive; and the optical orientation is X A c = 5° in acute angle 

 13, but whether Y or Z = 6 is uncertain. 



These properties, with but minor variations, are shown by 

 several different preparations made in this laboratory, by a 

 German product obtained before the war, and by the English 

 "sensitol green." The identity of all of the substances is thus 

 established. 



OKNlTHOhOGY .—Grandalidae, a new family of turdine Pas- 

 seriformes. Harry C. OberholsER, Biological Survey. 

 The genus Grandala was based by Hodgson on a unique new 

 species which had been obtained in Nepal and which was named 

 by him Grandala coelicolor.^ This beautiful and otherwise re- 

 markable bird has hitherto been referred to the Turdidae, usually 

 without question. It has commonly been considered most closely 

 allied to Sialia Swainson, and, indeed, by Seebohm- was even 

 made a subgenus of that group. It was evidently so placed 

 because of its booted tarsi, blue color, and general size, for in no 

 other important respect does it suggest Sialia. Even a casual 

 examination is sufficient to show that Grandala has, as Oates 

 long ago concluded,^ nothing to do with Sialia. In fact it does 

 not belong in the same family, nor, indeed, to any other currently 

 recognized family of passeriform birds, and it forms, consequently, 

 a very distinct monotypic group, which should stand as 



Grandalidae, fam. nov. ^ 



Diagnosis: Similar to the Turdidae, but bill motacilline, not turdine, 

 slender; tip of maxilla not hooked; basal portion of culmen straight or 



1 Journ. Asiatic Soc. Bengal 12: 447. June, 1843. 



2 Cat. Birds Brit. Mus. 5: 328. 1881. 



' Fauna Brit. Ind., Birds 2: iio. 1890, 



