1920] STEVENS— PORTO RICAN FUNGI 253 



extensive clypeus, then developing the stromata between this clypeus 

 and the palisade cells. Loculi globular or lenticulate, 100-250 n 

 in diameter, 80 /x high, by pressure sometimes pushing into the 

 mesophyll. Asci about 1 10X 1 7 /jl, cylindrical, 8-spored, inordinate. 

 Spores 20X7 ft, i-septate about one-third the distance from one 

 end, brown when mature. Paraphyses filamentous, branching. 



On Eapatoriiim portoricense, Dos Bocas below Utuado, 6866 (type), 6034, 

 6830,6437,6861,6032,6537. 



The clypeus is strictly epidermal, and under it very numerous loculi 

 develop, each with an ostiole reaching through the clypeus. The occasional 

 pressing of the perithecia into the mesophyll sometimes gives this the appear- 

 ance of closer relationship to the Phyllachorineae, but its relationship is clearly 

 with the Scirrhiineae. 



Halstedia, gen. nov. — Asci borne in a locule in a superficial 

 stroma. 



Type H. Portoricensis. Named in honor of Byron D. Halsted. 



Halstedia portoricensis, sp. nov. (figs. 18, 19). — Stromata 

 amphigenous but more abundant and larger above, densely black, 

 1-4 mm. in diameter, flat, with surface in the older parts corrugated, 

 or sometimes raised in the center, strictly superficial, non-radiate. 

 Perithecia up to 400 /i in diameter, 160 ju from base to top, internal 

 measurements. Asci 8-spored, 68-85 X 14 m, cylindrical. Spores 

 oval, continuous, hyaline or pale straw-colored, 17X10 ju- 



fungu 



foetidissimum 



200 



The stroma is flat-topped, the bulging due to the development of the perithe- 

 cium usually resulting in a downward thrust and displacement of the leaf 

 rather than of the upper layer of the stroma (fig. 16). In some instances the 

 reverse is true, with an upward bulging. Closest search failed to reveal any 

 evidence of penetration of the fungus through the epidermis, or of any mycelium 

 or signs of disease in any of the host cells. There is no ostiole, and the perithe- 

 cium is poorly developed, if indeed it is more than a locule in the stroma. The 

 fungus shows close kinship with the Dothideales, but cannot be placed in any 

 of the families of that order as characterized by Theissen and Sydow. It 

 differs from typical Perisporiaceae in the absence of a clearly developed perithe- 



a stroma. It forms an interesting transition form 



possessing 



pona 



ceous. 



