10 NORTH AMERICAN FAUNA. (No. 16, 
percentage of the common species and is, as expected, a stepping stone 
on which restricted Sierra and Cascade species overlap. But the rep- 
resentatives of the two ranges are not equally apportioned. The most 
evident gap is on the north, Shasta sharing many more species in com- 
mon with the Sierra than with the Cascades. Indeed, the resemblance 
to the northern Sierra is so exceedingly close, particularly in the mam- 
mal fauna, that from the standpoint of geographic distribution Shasta 
could without violence be classed as part of the Sierra. This is the 
more surprising in view of the fact that the geographical gap between 
Shasta and the Cascades is only half as broad as that between Shasta 
and the Sierra. This subject is discussed in detail in the chapters 
entitled ‘The Boreal fauna and flora of Shasta contrasted with corres- 
ponding faunas and floras of the Sierra and the Cascades,’ ‘Efficiency 
of Klamath Gap as a barrier to Boreal species compared with that of 
Pitt River and Feather River gaps collectively,’ and ‘Sources of the 
Boreal faunas of Shasta and of the Sierra and the Cascades.’ 
ITINERARY. 
Leaving the railroad at Sisson, at the west base of Shasta, we estab- 
lished the first camp July 15, 1898, at a point known as Wagon Camp, 
Via. 1.—Wagon Camp. 
on the south slope of the mountain, about a quarter of a mile west of 
Panther Creek, at an altitude of 5,700 feet (fig. 1). Wagon Camp issitu- 
