l6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4I 



total biotic relationships in the ecology of each species. Although 

 physically separated in this monograph, the many associates of each 

 species of cockroach should all be considered in appraising the ecology 

 of that species. To assist the reader to achieve this end, we have in- 

 cluded a checklist (p. 290) which serves as a convenient index to cer- 

 tain organisms associated with particular species of cockroaches. 



CAVE HABITATS 



Caves, mines, and animal burrows are somewhat similar habitats 

 that provide many species of cockroaches with shelter and frequently 

 with food. The microclimates of these cockroach habitats have not 

 been described in detail in the papers cited, but it seems rather obvious 

 that natural caves, man-made caves (mines), and burrows offer 

 relatively stable temperatures and humidities and protection from ad- 

 verse climatic conditions. Although such cavernicolous animals as 

 birds and bats periodically leave caves to search for food, cockroaches 

 find the accumulated guano and animal and plant detritus an entirely 

 adequate dietary (Chopard, 1938). Cockroaches in mines presumably 

 subsist on the food and feces dropped by man and mine animals 

 (e.g., pit ponies). Food stored in their nests by burrowing animals is 

 undoubtedly utilized by the associated cockroaches. 



Cavernicolous cockroaches show varying degrees of dependence on 

 and adaptation to these specialized habitats. Some of the common 

 domiciliary species {Blatta orientalis, Blattella germanica, and Peri- 

 planeta americana) may have accompanied man into caves and re- 

 mained there after he left (Chopard, 1929a, 1936, 1938). Other 

 species, from the paucity of records noting their occurrence in caves, 

 are undoubtedly accidental inhabitants that may never become estab- 

 lished. Besides these, however, many other species of cockroaches 

 have established large breeding colonies in caves. Although some 

 of the latter species show very pronounced morphological adaptations 

 to a cave life, many others resemble their noncavernicolous relatives. 

 The possible origin of cavernicolous Orthoptera has been discussed 

 by Chopard (1938). 



Cavernicolous cockroaches have been segregated into four groups 

 according to their ability to adapt to their environment and the degree 

 of their specialized evolution (Chopard, 1936, 1938) : (i) Troglox- 

 enes: Cockroaches that occur in caves in a sporadic fashion (the 

 domiciliary cockroaches and accidentals such as Ectohius and Hetero- 

 gamodes). (2) Troglophiles : Cockroaches found habitually in 

 caves {Symploce, Periplaneta cavernicola). (3) Guanobies: Cock- 



