SOME PHYLLACHORAS FROM PORTO RICO 



F. L. Stevens and Nora Dalby 



(with plates vi-viii) 



The following species were collected by the senior author, and 

 specimens are deposited as is indicated in an article by E. Young/ 

 The definition of the genus Phyllachora given by Theissen and 

 Sydow^ is accepted, and only species conforming to their concep- 

 tion of the genus are here listed. 



Phyllachora andropogonis K. and H. 



On Imperata contracta: Maricao, 8875, 8898; Rio Tanama, 8006; Arecibo- 

 Lares road, 7216. 



The spores are much larger than those of P. graminis, but agree well with 

 those of P. andropogonis. The stromata when young bear many Sepforia- 

 like conidia. 



Phyllachora banisteriae, sp. nov. — Spot none. Stromata 

 numerous, scattered evenly over the leaf, 1-2 mm. in diameter, 

 circular or more often oblong, black, visible from above and 

 below, usually poorly developed in the mesophyll; clypei both 

 above and below, thin, limited to the epidermis. Locules few^, large, 

 about 190X270 ju. Asci 8-spored, cylindrical. Spores oblong, 

 hyaline, continuous, 14X35 m- — Figs, i and 2. 



On Banisteria tomentosum: Vega Baja, 8341. 



Conidia, in pycnidia on the stromata, Septoria-Vikt. Differs from P. 

 pestis-nigra Speg. in many respects. 



Phyllachora bourreriae, sp. nov. — Spots none. Stromata 

 circular and black, abundant, scattered irregularly over the leaf, 

 1-2 mm. in diameter, equally prominent above and below, occupy- 

 ing the mesophyll. Clypeus in epidermis above and below, but 

 slightly exceeding the perithecia. Locules several, globular, about 

 160 /i in diameter, wall definite. Stroma in the mesophyll loose. 

 Asci cylindrical, 8-spored, 85X9-12/1. Spores hyaline, i-celled, 

 12-16X6-7 fx. — Figs. 3 and 4. 



On Bourreria succulenta: Vega Alto, 4149 (type); Joyuda, 477oy. 



'Mycologia 7: 143. 1915. ' Ann. Myc. 13: 149. 1915. 



Botanical Gazette, vol. 68] * [54 



