PALLAS'S SAND-GROUSE. 397 



were obtained on tlie Norfolk coast. I doubt wbetlier 

 the sand there would afford such large grains. They 

 may have been picked up on their native steppes, and 

 probably the same stones may remain in the gizzard for 

 an indefinite length of time. The stones, so far as one 

 can see, seem to be fragments of quartz and felspar, 

 and are therefore probably granitic. I have shown them 

 to one of our best geologists, an F.G.S., who concurs 

 with me, and thinks that nothing decisive can be pre- 

 dicted from them. They could all be easily matched in 

 England." I may here add that the later specimens 

 dissected by myself, had fewer flinty particles in their 

 gizzards, and those much smaller in size and more 

 mixed with sand. In the early examples, the size, and 

 peculiarly angular appearance of these white fragments, 

 would attract the notice of any one accustomed to 

 examine the internal economy of granivorous birds ; and 

 as it is generally understood, that such stones are 

 retained in the gizzard so long ^s their triturating 

 powers remain unimpaired by the action of the stomach, 

 it is most likely that on their first arrival our Tartar 

 visitants contamed their native grindstones. 



From an examination of just thirty specimens, 

 consisting of fourteen males and sixteen females, I 

 was particularly struck with the general similarity 

 of the specimens according to sex. The less matured 

 males differed only from those more adult (judging from 

 the largely developed state of the testes) in having the 

 ground colour of the plumage somewhat duller, and 

 their darker markings less clearly defined; but the 

 extremely dark tints of some old males, especially in the 

 deep grey of the breast, and more clouded appearance 

 of the wing coverts, were, I imagine, attributable to old 

 and somewhat soiled feathers, which in a few weeks 

 would have been replaced by others. In one or two 

 fine old males, very recently killed (for the brighter 



