4 Entomology and Zoology Department. [Bull. 168 



The following data apply to the first 100 moles taken at 

 Manhattan during the progress of these experiments : 



AVERAGE DIMENSIONS AND WEIGHT. 



Males (45 specimens) : 



Average total length, 176 mm. (about 7 inches). 



Average length of tail, 30 mm. (about l%e inches). 



Average weight, 4 ounces. 

 Females (55 specimens) : 



Average total length, 168 mm. (about 6% inches) . 



Average length of tail, 30 mm. (about l%e inches). 



Average weight, 3 ounces. 



In contrast to the slight variation in size among moles 

 taken in the same locality is the marked variation in color. 

 The dominant shade is a mingling of lead color and brown, but 

 some specimens are darker than this and, on the other hand, 

 some are a beautiful slivery gray, or perhaps are tinged with 

 purplish. At least two were taken that were suffused all over 

 with rich golden brown. On the average about one-half of the 

 moles taken here have certain regions of the body particu- 

 larly the nose, chin and breast washed with a tinge of orange 

 or have distinct patches of this color on the head or belly. 

 Some of these patches are yellowish or golden brown instead of 

 orange, and occasionally one is nearly white. A common 

 marking is a band on the nose. The patches vary in size from 

 a mere streak to a blotch covering almost the entire area of the 

 belly or head. The following data on color markings are from 

 the same 100 moles discussed under the head of average di- 

 mensions and weight: 



Males: 



Number having orange or rusty brown markings 27 



Number marked on nose only 5 



Number suffused or washed in part 18 



Number having well-defined patches 6 



Females : 



Number having orange or rusty brown markings 23 



Number marked on nose only 12 



Number suffused or washed in part 2 



Number having well-defined patches 9 



The distribution of moles seems to depend very largely upon 

 the humidity of the climate and consequent condition of the 

 soil in any particular region. As will be shown later, the mole 

 thrives best in a loose, moist soil, abounding in grubs and 

 earthworms. The hard, compact surface earth of arid and 



