MAMMALS OF PENNSYLVANIA AND NEW JERSEY. 199 



the mountain below the boreal summit, as in the case of the one from N. 

 Carolina mentioned next in the table. This is confirmatory of my own in- 

 vestigations in the region named. It is also confirmatory of the correctness 

 of Dr. Allen's faunal scheme so far as it relates to this region and of the in- 

 correctness of Dr. Merriam's map mentioned by True, which includes the 

 entire Pa. Alleghenian region in the "transition fauna." Dr. True's map of 

 the Northern distribution of Scalops along the southern shore of Lakes Erie 

 and Ontario, so far as it relates to Pa., Ohio and N. York, is, in the light of 

 subsequent investigations, proved to be faulty, the Star-nosed and Brewer's 

 moles being the only ones certainly recorded from these regions to my knowl- 

 edge. The character of the evidence on which Dr. True included any part 

 of the region north of the Great Lakes and the St. Lawrence, so far as given 

 in his " Revision," is equally untrustworthy. Everything points to a more or 

 less complete Alleghenian barrier, separating northern S. aquaticus, typicus 

 from its western representatives, the only land connection being made around 

 the southern end of the Allegheny system in northern Georgia. 



Habits, etc. The common naked-tailed mole of the region east of the 

 Alleghenies seems to prefer open grounds to woodland, and is practically 

 absent from large hemlock forests even in the lower transition zone. Alluvial 

 soils, devoid of rocks and stones, they most delight in, but wherever the earth- 

 worm abounds, even in rocky and gravelly places, the mole follows suit in pro- 

 portionate numbers. I have seen their characteristic sand heaps, by which their 

 work may be distinguished from that of the mole shrew and the pine mouse, 

 in the midst of the N. J. pine forests. In such places, however, the earth- 

 worms are very rare, and some other animal food must have been the attrac- 

 tion. The incessant digging, or rather ploughing of the mole, is accom- 

 plished almost solely by the use of the fore-legs and head, the weak hind legs 

 being merely props in comparison. The fore-legs are nearly all feet in an 

 external view, the powerful, short, massive shoulder and arm being hidden 

 wholly by the contour of the body. When burrowing is going on the pig-like 

 snout is set on a level with the bottom of the burrow, the shovel-like paws are 

 extended directly forwards with their long nails against tip of nose on each 

 side, and with a simultaneous upward throw of the nose and sidewise strokes 

 of the paws, the earth is forced upward and sidewise as with a wedge. In 

 surface digging and in moist, loamy soils, the earth is merely compacted lat- 

 erally and raised vertically without extraordinary effort, not making conspicu- 

 ous surface ridges, but when they must go deeper and in hard clayey or dry 

 soils the strength exerted must be enormous, and where too solid for the com- 

 pacting wedging process the soil must be removed by other means. In the 

 mere traversing of this sort of ground the soil can be packed behind the ani- 

 mal, but as they generally wish to have a back door escape in emergencies, 

 the burrow is completed by forcing the earth to the surface along lateral and 



