Masked Shrew 
263 
FIG. 79. UPPER JAWS AND TEETH OF SHREWS 
I. Sorex obscurus. 2. Sorex tenellus nanus. 3. Sorex personatus. 
4. Sorex va grans dohsoni 
Enlarged eight times. After Merriam 
It has been taken nearly to 11,000 feet, and I have seen a shrew 
of some species at 12,000 feet. While this book has been in press 
I have identified specimens from the Summit House on Pike's 
Peak, 14,147 feet altitude. 
Habits. — All the shrews of this genus are much alike in their 
