LEPORID.E— LEPUS TROWBRIDGE! 



345 



The variations in size in Lepus trowbridgei are well indicated in the 

 subjoined tables of measurements of the skulls and external dimensions. The 

 extremes in a series of ten skulls are: length, 2.28 and 2.55; width, 1.15 and 

 1.32; nasal bones (length), 0.90 and 1.17; lower jaw (length), 1.42 and 1.73. 

 The length of the ear varies in different specimens from 2.28 to 3.05, the 

 average being about 2.50 to 2.75. In specimens from the most southern 

 localities, the ear averages considerably longer than in those from the north- 

 ward, although the size of the animal, as indicated by measurements of the 

 skull, is smaller at the southward. Thus the average length of four skulls 

 from localities near San Francisco is 2.50 and the breadth 1.28; while the 

 average length of the skull in four specimens from Cape Saint Lucas is 2.29, 

 and of the breadth 1.17. 



The habitat of Lepus trowbridgei, as indicated by the specimens in the 

 present collection, seems to be restricted to the region east of the Cascade 

 range of mountains, and to extend along the coast from Fort Crook to Cape 

 Saint Lucas. 



Lepus trou-bridgei was first described by Professor Baird in 1855, and 

 redescribed by him under the same name in 1857, by which appellation it 

 has fortunately been always known. Very few original references have been 

 made to the species aside from those in the various reports of the Pacific 

 Railroad surveys and explorations. 



Table XLII. — Measurements of L. trowbridgei. 



' Specimens from Museum of Comparative Zoology. Cambridge, Maes. 



