216 PROCEEDINGS OP THE AMERICAN ACADEMY 



cluster protrudes from a crater-like opening, which was formed by 

 rupturing and reflecting the epidermis in much the same manner as in 

 a. glandulcBformis. The individual 'heads agree with those of the 

 latter species in having practically the same structure ; the spore-mass 

 in longitudinal section (Fig. 20) shows the lateral and internal and 

 external central cells arranged upon the same plan as in R. glayidula;- 

 formis ; one cyst-cell underlies each spore-cell in the base of the spore- 

 mass ; the stalk is compound, and the relation of its cells to the cysts 

 is the same as in R. glandulceformis. What has already been said of 

 the morphology of the American species will doubtless apply with 

 equal force to R. glabra. 



A third form which will come under the present group is a species 

 which was described by the Rev. Mr. Berkeley as R. sessilis, and 

 which was found upon Acacia Lebhek in Ceylon. The Curtis collec- 

 tion contained one specimen of this species, from which the head (Fig. 

 15) was taken. This specimen, together with others, was carefully 

 studied, and, aside from the difference in the host and locality, no dis- 

 tinguishing mark could be found between it and R. glandulceformis. 

 The spore-mass, cysts, and compound stalk agreed in detail with those 

 of the American species, and we were unable by any structural peculi- 

 arity to distinguish them. 



In addition to the Ceylon material, Ravenel's " Fungi Americani 

 Exsiccati " contained a specimen labelled, " Ravenelia sessilis, Berk., 

 in foliis Tephrosice, Aiken, S. C," and it was through this specimen 

 that R. sessilis had been attributed to America. Figure 1 6 represents 

 a head from the Ravenel Exsiccati, and here, as in the previous case, a 

 diligent search failed to bring to light any character distinguishing this 

 from R. glandulceformis. Neither the host nor the locality in this 

 case could serve to separate them, and consequently we can see no 

 reason for considering them distinct. 



It is then hardly open to doubt, that R. sessilis as distributed by 

 Mr. Ravenel is R. glandulceformis, in which perhaps a majority of the 

 ripened heads have broken from the stalks, as has already been ex- 

 plained, and appear on the leaflet in this stalkless condition. As we 

 have before remarked, the Ceylon R. sessilis can only be distinguished 

 from R. glandulceformis by the difference of its host and habitat, and 

 not by any structural peculiarity. \Yhat the specific value of these 

 characters is we leave to those better able to judge ; for ourselves, 

 we must candidly admit that, even in the case of the Ceylon R. sessilis, 

 we do not see reasons enough for considering it distinct from R. glandu- 

 lceformis. 



