MONOGRAPH OF TTIE LABO ULBENIACEvE. 



243 



Total number of species known to exist 158 



« " " u described 152 



" " " North American species described 124 



" " " Nortb American species known 130 



" " " European species 19 



" " " African species 14 



" " " South American species 6 



" " " Asiatic species * 6 



" " Australian species * 2 



Common to North America and Europe. — Chitonomyces paradoxus, Rhadinomyces pallidus, 

 Lahoidbenia elongata, L. cristata, L. Gryrinidarum, L. luxurians, L. Nebrio3, L. subterranea, L. 

 vulgaris. 



Common to North America and South America. — Laboulbenia Guerinii, L. variabilis, L. 

 polyphaga. 



Common to North America and Africa. — Laboulbenia Catascopi, L. polyphaga, L. elongata (?). 

 Common to South America and Africa. — Laboulbenia Pheropsophi, L. polyphaga. 

 Common to Africa and Asia (Japan). — Laboulbenia pr oil ferans. 

 Common to North America, South America, and Africa. — L. polyphaga. 

 Common to North America, Africa, Europe, and Asia. — Laboulbenia elongata. 

 Common to North America, Europe, and Asia (?). — Laboulbenia vulgaris. 



In regard to the distribution of single species in a given continent no data are 

 available in any case except that of North America, where a wide distribution of given 

 species is indicated. The common Laboulbenia NebricB, which is also known to occur in 

 Europe, is found in America from Maine to Virginia, and west to Washington, extend- 

 ing northward to Alaska and the Aleutian islands. Laboulbenia cristata is another 

 instance of a European form which is found in this country from Maine to 

 Nicaragua, and several examples might be mentioned of species found throughout the 

 United States and Mexico. The writer has unfortunately had no opportunity of col- 

 lecting Laboulbeniaceoe on their living hosts outside of New England, and it is only 

 in this limited territory that an approximate knowledge of their local distribution has 

 been obtained; yet in general it may be safely assumed that the different species have 

 a range practically coincident with that of their usual hosts. The occurrence of more 

 or less cosmopolitan forms, like some of those mentioned above, which are doubtless 

 more numerous than our present knowledge would indicate, has a certain interest 

 when we consider that the possibilities of dissemination are so restricted as is neces- 

 sarily the case where, as in the present instance, direct transfer from one living host 

 to another is an essential factor in the perpetuation of the species. Of the more local 

 occurrence of the Laboulbeniacese nothing further need be said at present, since, as 

 has just been mentioned, it coincides with that of the special hosts of the group, which 

 will be presently referred to. 



