JACKSON — STATUS OF MBRRIAM^S SHREW 
29 
THE STATUS OF MERRIAM^S SHREW (SOREX MERRIAMI) 
By Hartley H. T. Jackson 
There is so little generally known about the shrews Sorex merriami 
Dobson and Sorex leucogenys Osgood, that a brief summary of our present 
knowledge of these two forms might not be amiss and might stimulate 
men doing zoological field work to, make a special effort to secure more 
of these rare mammals and learn something of their habits. 
Once one has become familiar with these two shrews they are com- 
paratively easily distinguished from other forms. In size they are some- 
what larger than individuals of Sorex personatus, rather pale (a grayish 
drab above), and with distinctly whitish underparts and feet. The skull 
is relatively short and broad, flattened through the braincase but rela- 
tively high and swollen interorbitally, with a short, broad rostrum, which, 
compared with that of other members of the genus found within its 
geographic range, is abruptly truncate anteriorly (nares region). The 
third upper unicuspidate tooth of most of the west American shrews is 
smaller than the fourth. Exceptions to this are found in Sorex per- 
sonatus and Sorex richardsonii, both species which may possibly occur 
within certain parts of the geographic range of shrews of the merriami 
type, and, like them, have the third upper unicuspid larger than or, 
infrequently in personatus, equal to the fourth. Both merriami and 
leucogenys, however, have the unicuspids relatively narrow and elon- 
gate, and tending to be more crowded together than in personatus or 
richardsonii. A glance at the accompanying figures will enable one to 
grasp some of the differences in the rostra and dentition. In the scanty 
material available there appears no difference in color between mer- 
riami and leucogenys. The latter, however, is slightly larger than 
merriami and. shows cranial differences in being distinctly higher 
through the braincase and having the anterior halves of the unicus- 
pidate tooth rows less approximated and less nearly parallel. 
The type-specimen, an adult female, skin and skull in good con- 
dition, is the only known specimen of Sorex leucogenys. It was caught 
August 12, 1908, about 200 yards from running water on a dry rocky 
Upper Sonoran slope, where the vegetation was scant and practically 
restricted to Juniperus, Artemisia, and Atriplex, about 3 miles east of 
Beaver, Beaver County, Utah (Osgood, W. H., Proc. Biol. Soc. Wash- 
ington, vol. 22, p. 52, April 17, 1909). 
The type-specimen of Sorex merriami is an alcoholic with skull 
removed. The skull is practically perfect. It was collected by Maj. 
