166 University of California Publications in Zoology I'^o^- 24 



southeast of Telegraph Creek ; if algidus occurs in that range it should 

 be at Telegraph Creek also. 



We obtained several long-tailed specimens of Peromyscus at and 

 near Telegraph Creek, and supposed that they were examples of 

 algidus. Study of the series as a whole, however, inclines me to an- 

 other explanation of the variation, that seems more satisfactory, 

 namely, that there is continuous distribution of Peromysctis along the 

 Stikine Valley, from the habitat of loreaUs in the interior to that of 

 macrorhinus on the coast, that there is intergradation between these 

 two subspecies in the Stikine Valley, that Telegraph Creek is about 

 the easternmost point to which intergrades with macrorhimus extend, 

 and that the variants obtained by us at that point are all the results 

 of intergradation. 



The long-tailed individuals from the Telegraph Creek region, aside 

 from this peculiarity, are not notably different in color or otherwise 

 from the general run of specimens obtained there. At any rate, they 

 could not be grouped together as presenting an aggregation of char- 

 acters justifying their separation as a distinct subspecies. Neither 

 were they obtained under circumstances that would tend to establish 

 the belief that two different races were concerned. 



The Peromyscus taken at the Junction are lighter colored than 

 macrorhinus of the coast, and they are smaller and shorter tailed. This 

 station is some five miles north of the Stikine River ; presumably these 

 mice are more nearly typical of horealis than any others we obtained. 

 In this series there is one aberrant individual with an exceedingly 

 long tail ; otherwise there is great uniformity in the lot. At the town 

 of Telegraph Creek we obtained more long-tailed mice, and noted a 

 slight increase in general size, as compared with the series from the 

 Junction. Descending the Stikine River from Telegraph Creek, the 

 Peromyscus collected at our various stations were progressively larger 

 and darker colored as the coast was approached. 



The accompanying diagrams (figs. R, S, T) show variation in hind 

 foot, length of tail vertebrae, and ratio of tail vertebrae to total length, 

 in the white-footed mice taken at our various collecting stations in the 

 Stikine region, as compared with macrorMnus of the Alaskan coast. 

 Color and general size vary in about the same way as the characters 

 illustrated. Barring the series from the Junction, which are probably 

 close to true horealis, the Stikine River Peromyscus are typical of 

 neither horealis nor macrorhinus. They form a series of intergrades 

 between the two. It is not possible to draw a hard and fast line as a 



