CERAMBYCID BEETLE FAUNA 



309 



from the Vancouveran, and Gaurotes is represented by only a single 

 species in that subfauna. 



The present Alleghenian subfauna is not, however, entirely 

 composed of northern elements. A few southern derivatives became 

 established at a date early enough for them to persist as endemics, 

 e.g., the clytine genera Glycohius and Sarosesthes, and the lepturine 

 genera Bellamira, Charisalia, and Strangalia. Several Neotropical 



Table IV. Discontinuous Distribution of Some Holarctic Genera of 

 Cerambycidae Differentially Represented in the Vancouveran and 

 Alleghenian Faunas of North America" 



« Numerals indicate approximate numbers of known endemic species. 



genera e.g., Neoclytus, Leptostylus, Lepturges, and Leiopus, also give 

 evidence of having come into the fauna at an early date, and indeed, 

 some of these are represented in the fossil beds at Florissant. The 

 early southern elements may be eastern counterparts of the "Cal- 

 ifornian" discussed below, but in the absence of climatic barriers 

 that have maintained the integrity of the "Californian" they have 

 apparently blended with the northern Alleghenian elements and 

 shared their late Tertiary geological history. 



The Vancouveran subfauna (Van Dyke, 1919, et seq.), in its 

 purest form, occurs along the coast of western North America from 

 the Aleutian Islands to central California, more broadly in the 



