FUNGI. 479 



margins. Physcia integrata sorediosa Wainio and Py'xine picta (Sw.) 

 Tuck, agree in having narrow lobes, with the soredia in soralia (powdery 

 pustules) ; but in the latter the thallus is more closely appressed to the 

 substratum and has confluent lobes. 



SUMMARY OF GEOGRAPHICAL AFFINITIES. 



The results of an analysis of the geographical range of the species 

 making up the lichen-flora of Bermuda may be shown in the following 

 table : 



Endemic 10 



Occurring in the West Indies or Tropical South America, but not in 



the United States 14 



Occurring in the West Indies and also in the southern United 



States 29 



Occurring in the southern United States but not in the West Indies. 

 Widely distributed in the Temperate as well as in the Tropical 



Zone 21 



Typically northern species not known in Tropical regions 4 



(Note: The difference in the total number given here and in the 

 introduction is due to the omission of certain unimportant varieties.) 



An inspection of the table will show clearly that the lichen-flora of 

 Bermuda is most closely related to that of the West Indies. The rela- 

 tively northern position of the islands, however, permits of the growth of 

 four species of colder countries, that are not found in the West Indies. 

 Finally, the peculiar conditions existing in Bermuda have resulted in a 

 comparatively large number of endemic species. 



Class 2. FUNGI. 



MOULDS, BLIGHTS AND MUSHROOMS. 



CONTRIBUTED BY FRED J. SEAVER. 



INTRODUCTION. 



The fungi, which are more commonly known under such names as 

 puffballs, mushrooms, mildews or moulds, constitute a group of plants 

 which are represented in the entire world by more than fifty thousand 

 species. They are often referred to as degenerate plants, the term degen- 

 erate being applied more on account of their habits of life than because 

 of their simplicity of structure, for while many of them are simple, many 

 others show much complexity in general structure as well as in their repro- 

 ductive processes. 



Probably the inability of the fungi to manufacture their own food, as 

 is done by the higher green plants, together with the fact that many of 

 them are small and grow in out of the way places, often living as scaven- 

 gers on decaying matter, has done more to cause them to be looked upon as 

 degraded forms of vegetation than any simplicity or peculiarity of struc- 

 ture. Whether as a cause or a consequence, the fungi are entirely devoid 

 of green coloring matter or chlorophyll, and are therefore dependent upon 



