302 Field Columbian Museum — Zoology, Vol. III. 



FAM. HETERQMY] DM. 

 Sub. Fam. Dipodomyin^e. 

 DIPODOMYS. 

 Dipodomys merriami nitratus. 



Dipodomvs m. nitratus Merr., Proc. Biol. Soc. Wash., il 

 p. 112. Elliot, Syn. X. Am. Mamm., 1901, p. 233. 



16 Examples: 6 Keeler (topotypes), 10 Lone Pine. 



"The sand dunes near Owens Lake in the vicinity of Keeler 

 were perforated with the tunnels of this local form. As the 

 animal recedes from the hot sandy shores of the lake, it becomes 

 less reddish, and it is evident that the typical form does not 

 extend more than fifteen or twenty miles from the shore line." 

 Most of the mammals from this locality are characterized bv 

 greater depth of coloring than those from elsewhere, and speci- 

 mens from Keeler or the lake are much richer in hue than speci- 

 mens of the same species taken at a distance. These animals from 

 the Owens Lake region exhibit in a striking degree the effects of 

 environment upon color, and local varieties are produced, though 

 without doubt the individuals are specifically the same as those 

 living twenty miles away and which have a less ornate dress. But 

 according to the custom of the day these variations must be 

 dignified with a separate name, and they are in fact more easily 

 recognizable among other specimens of the genus than man}' a 

 one bearing a subspecific appellation, but which unhappily has 

 no especial coloration to separate it from its fellows. In such 

 cases faith has much to do with the determination. Some of 

 the Lone Pine specimens are considerably paler than those from 

 Keeler. 



Dipodomys merriami simiolus. 



Dipodomvs m. simiolus Rhoads, Proc. Acad. Nat. Scien. Phil., 

 1893, p. 410. Elliot, Syn. Am. Mamm., iqoi, p. 234. 



Dipodomys m. similis Rhoads, Proc. Acad. Nat. Scien. Phil., 

 1893, p. 411. Elliot, Syn. N. Am. Mamm., 1901, p. 234. 



54 Specimens: 20 Palm Springs (topotypes of IK m. simiolus), 

 12 Whitewater (topotypes of D. m. similis), 6 Morongo Pass, 

 4 Burns Canon, 1 Warren's Well, 3 Old Woman's Spring, 2 Oro 

 Grande, 1 Calico Mountains, 5 Daggett. 



With so manv topotvpes of D. m. simiolus and D. m. similis 

 from Palm Springs (xVgua Caliente) and Whitewater, I do not 



