CERAMBYCID BEETLE FAUNA 311 



(Fig. 1). These are the dominant Cerambycidae of the Transition 

 Life Zone of Merriam (1898) and show closer afifinities with those of 

 Europe and eastern Asia than with their Alleghenian counter- 

 parts in eastern North America. Thus, in the Vancouveran subfauna, 

 we find the endemic Opsimus and Dicentrus (only New World 

 Saphanini), Synaphaeta (only New World genus of Mesosini), 

 and Brothylus, Leptalia, Ulochaetes, Hybodera, and Lophopogotiius, 

 all with related genera in the Old World. Several other genera 

 share species with both the Vancouveran subfauna and those of the 

 Palearctic Region, but not the Alleghenian (Table IV). These include 

 Plectrura (one species in Japano-Manchurian region, one in Van- 

 couveran) ; Spondylis (one species Palearctic, one Vancouveran) ; 

 Megasemum (one species in Japano-Manchurian, one in Vancouver- 

 an) ; Callimellum (eight species in southern Europe and Asia Minor, 

 two in Vancouveran) ; Cortodera (numerous species in both Europe 

 and Vancouveran) ; Xylosteus (one species in southern Europe, one 

 in Vancouveran) ; and Rosalia (one species in Japano-Manchurian, 

 two in south China, one in Europe, one in Vancouveran). Other 

 genera endemic in the Vancouveran fauna are Xylocrius (two 

 species), Poecilobrium (one species), Enmichthus (one species), 

 Holopleura (one species), Ortholeptura (three species), Piodes (one 

 species), and Pyrotrichiis (one species). Presumably all these have 

 ancient northern affinities. 



The relict trees of the genus Sequoia, growing within the area 

 occupied by the Vancouveran subfauna, are hosts of several endemic 

 cerambycid species or subspecies (all members of the tribe Callidini). 

 These include Callidium vandykei Linsley, C. sempervirens Linsley, 

 and Semanotus ligneus sequoiae Van Dyke, which are limited to the 

 coast redwood {Sequoia sempervirens), and Callidium sequoiae 

 Fisher, on the big tree [S. gigantea). A more striking group of 

 Cerambycidae is found on the Sargent Cypress (Cupressus sargentii) 

 which grows only in a few restricted areas of serpentine rock in the 

 foothills of northern California. Confined to this host are Vatidykea 

 tuber culata Linsley, Atimia helenae Linsley, and Callidiellum cup- 

 ressi (Van Dyke). The last species has a close relative, C. rufipenne 

 (Motschulsky, in Japan, associated with Crytomeria japonica and 

 Chamaecyparis obtusa, another, C. villosulum (P^airmaire), in China, 

 on Cunninghamia lanceolata, all members of the Cupressaceae or 



