THE SAGE GROUSE. HI 



" In western Wyoming the Sage Grouse packs in September and October. 

 In October, 1886, when camped just below a high bluff on the border of 

 Bates Hole, • in Wyoming, I saw great numbers of these birds, just after sun- 

 rise, flying over my camp to the little spring which oozed out of the bluff 

 200 yards away. Looking up from the tent at the edge of the bluff above 

 us, we could see projecting over it the heads of hundreds of the birds, and, 

 as those standing there took flight, others stepped forward to occupy their 

 places. The number of Grouse which flew over the camp reminded me of 

 the oldtime flights of Passenger Pigeons that I used to see when I was a 

 boy. Before long the narrow valley where the water was, was a mov- 

 ing mass of gray. I have no means whatever of estimating the number of 

 birds which I saw, but there must have been thousands of them." 



According to my own observations, confirmed by that of several other 

 observers in widely different localities, the number of eggs laid by this 

 species usually varies from seven to nine, and I consider eight a fair aver- 

 age number. In sixteen nests examined by me, but one contained ten eggs, 

 three contained nine each, six contained eight eggs, four but seven each, 

 and two less, unquestionably incomplete sets. Mr. W. S. Rougis, of Wyo- 

 ming, gives the number as from ten to fourteen. Mr. W. M. Wolfe, writes 

 me that the average number is fifteen, and that he has found seventeen eggs 

 in a nest of this species. I have no reason to doubt the correctness of these 

 statements. It only shows that no fixed rule can be laid down in such 

 matters, and what will be found a usual set in one section, or in one season 

 even, will not hold good in another. 



The eggs of the Sage Grouse vary in shape from ovate to elliptical 

 ovate and elongate ovate. The coloring matter is all superficial, and easily 

 wiped off on a freshly laid egg, leaving the shell greenish white in some of 

 the specimens and a pale pea green in others. The ground color varies 

 from an olive buff-with a greenish tinge, in a few specimens, to ecru drab 

 and greenish brown. They are more or less heavily spotted with well rounded 

 and sharply defined spots of chocolate brown, ranging in size from a No. 2 

 shot to that of mustard seed. The markings vary considerably in amount, 

 some eggs being profusely spotted, while others are but faintly so. 



The average measurement of one hundred and nine specimens in the 

 U. S. National Museum collection is 55 by 38 millimetres. The largest egg 

 of the series measures 59.5 by 39.5, the smallest 52 by 36 millimetres. 



The type specimens selected to show the differences in size, as well as 

 in the ground color and markings, were obtained as follows: No. 17385 (PI. 

 3, Fig. 11), selected from a set of nine eggs, was collected by Mr. F. A. Hirst, 

 near Fort Bridger, Wyoming, May 10, 1877; No. 21095 (PI. 3, Fig. 12), 

 from a set of eight eggs, was taken near Camp Harney, Oregon, May 28, 

 1876; and No. 21096, (PL 3, Fig. 13), from an incomplete set of five eggs, 

 was taken near Malheur Lake, Oregon, on April 4, 1877. The last two are 

 from the Bendire collection. 



