Chardon : Pyrenomycetes of Porto Rico 



287 



The systematic position of the genus is not definitely established. 

 It is included in the Hypocreales by Seaver (24) as a synonym 

 of Balansia. Since Seaver does not discuss any of the species of 

 Dothichloe under Balansia, there appears to be no justification for 

 this. Dothichloe is distinct from Balansia in not possessing a 

 pseudosclerotium made up of a mixture of host and fungous tissue. 

 Theissen and Sydow (39) exclude the genus from the Dothideales 

 and regard it as identical with Ophiodothis. Stevens in his 

 " Fungi Which Cause Plant Disease " assigns it a definite place in 

 the Hypocreales, placing it next to Balansia. The writer has ex- 

 amined a set of prepared slides made from the type specimen of 

 Hyp ocr ea atr anient osa B. & C. which are deposited in the Atkin- 

 son herbarium at Cornell University. The stroma is evidently 

 dothideaceous and no evidence of a perithecial wall is present. 

 However, in their filiform spores and in certain other minor char- 

 acters the species show marked resemblance with those of Balansia, 

 Epichloc and Hypocrella, and thus a relationship with the Hypo- 

 creaceae is strongly suggested. 



Key to Porto Rican Species 



A. Stromata distinct, subglobose, located below the nodes of the host. 



D. subnodosa 



B. Stromata broadly effused. 



1. Stromata completely encircling the culms. D. Aristidae 



2. Stromata borne on the leaf and occupying only one side. 



D. atramentosa 



Dothichloe subnodosa sp. nov. 

 Balansia subnodosa Atk., in mss. 



Dothichloe nigricans (Speg.) Seaver, in Stevenson, Jour. Dept. 

 Agr. Porto Rico 2: 151. 1918. 



Stromata subglobose, slightly flattened, located just beneath the 

 nodes on the culms of the host, partially or in rare cases entirely 

 surrounding the host, black, brown or yellowish within, not united 

 with the host elements, 1-3 mm. in diam., with the surface rugulose 

 from the papillate ostiola; locules immersed, flask-shaped, 125- 

 150 x 150-200 /jl; asci narrowly cylindrical, tipped with a globose 

 "cap cell," 150-180 x 3-4.5 n, 8-spored ; spores filiform, nearly as 

 long as the asci, approximately 1 fx broad, fragmenting at maturity ; 

 paraphyses present (fig. 14). 



