FUSCUS. CONTEXT BROWN. 



FOMES EXTENSUS. Pileus applanate, thin, 4-5, mm. thick, 

 with a thin, black crust. Surface brown, dull, with raised zones. 

 Context dark brown, hard. Pores very minute, concolorous, not 

 stratified (in the type). Setae short, thick, with swollen base. Spores 

 hyaline, perhaps pale colored, globose, 4 mic. 



The type at Paris from Guadeloupe is all that is known to me. It 

 closely resembles thin species of Fomes senex, but the spores are 

 hyaline, and the setae of a different type. Murrill refers many col- 

 lections from the West Indies to Fomes extensus which should have 

 been referred to the species he "discovered" Fomes pseudosenex. 



SECTION 71. CONTEXT BROWN. SETAE, NONE. SPORES COLORED. 

 A. Context Light Brown. 



FOMES RIMOSUS. Pileus unguliform, with a black, rimose 

 surface, usually very rough, no distinct crust. Context bright yellow 

 brown (Raw Sienna). Pores minute, hard, annual layers 3-4 mm. 

 thick. Pore mouths concolorous, when young velutinate to touch. 

 Hyphae deep bright yellow. Setae, none. Spores globose, deeply 

 colored, 5 mic. 



The early history of this species is obscured by having been con- 

 fused by its author (cfr. Fomes scabra). However, it proved a fre- 

 quent species in many countries, and has been generally known to all 

 mycologists for years under this name. It is the plant so referred in 

 Fries' work and mostly Berkeley's, Cooke's, as well as most American 

 authors. It is most abundant in the United States on the locust tree 

 (Robinia) in the Middle West. In the East there are sections where 

 it is more rare. Although the locust is very common as an ornamental 

 tree in Europe (known around Paris as Acacia), this Fomes is only 

 known in Europe from one specimen, now in Upsala, collected by 

 Fautrey in France. The disease has not become established on the 

 locust tree in Europe as it has with us in America. Fomes rimosus 

 occurs also in various tropical countries. We have seen specimens 

 from Jamaica, Mauritius, South Africa, India, Samoa, Ceylon. 



SPECIMENS. Typical United States. Many collections, it being the common Fomes on 

 the locust tree. 



South Africa Dr. H. Becker, I. B. Pole Evans, W. T. Saxton. It appears common in South 

 Africa and exactly the same as United States form. 



Samoa C. G. Lloyd. Rare in Samoa. Only one collection was made, which grew on a large 

 liane of the Leguminosae family. 



New Caledonia Specimen from Museum, Paris. 



Ceylon Fetch, 3596 and 3597. 



DEPARTING FROM TYPE FORM. 



Ceylon Fetch, 3598. Surface paler, not rimose. No. 2781, crust black and smoother and 

 shape applanate. 



New Caledonia Ex. Museum, Paris. Context darker and shape more applanate. 

 Australia E. C. Stirling. Shape narrow, ungulate, and pores slightly larger. 



. ILLUSTRATION. Our figure 590 of Fomes snuarrosus could also be used to illustrate this 

 species. For the camera, they are both the same. 



Compare Cedrelae, endotheius, ignarioides, Robiniae, rudis, tuniseus. 

 248 



