AN UNDESCRIBED SPECIES OF OPHIO- 

 DOTHELLA ON FICUS 



Ernst A. Bessey 

 (With Plate 5) 



The fungus herein described was collected repeatedly by the 

 writer in the vicinity of Miami, Florida, in 1907 and 1908. It 

 was recognized as an apparently undescribed Dothideaceous 

 fungus, but until the appearance of the monograph on that group 

 by Theissen and Sydow its generic position, even, could not be 

 determined. 



Ophiodothella Fici sp. nov.^ 



The stromata are i to 10 mm. in diameter, scattered irregularly 

 or sometimes grouped concentrically, extending from the upper 

 to the lower surface of the leaf, shining-black on the lower sur- 

 face, usually long covered by the wrinkled remains of the epi- 

 dermis and cuticle on the upper surface, which give it a whitish 

 appearance. This coat disappears in old specimens and is often 

 ruptured irregularly or pierced by the ostioles of the pycnidial 

 cavities. The leaf is much thickened. Normally it is about 450 fx 

 thick but the diseased spots may be 650 to S60 fx in thickness. 



Three layers may be distinguished in the stroma : ( i ) between 

 the upper epidermis and the palisade cells, usually destroying the 

 inner two layers of the mostly three-layered epidermis, about 100 

 to 180 /X thick, light-colored and thinner near the edges and very 

 dark and thicker toward the center, especially in proximity to 

 the pycnidial cavities. The two-layered palisade parenchyma 

 occupies about 100 to 120 /x, and is little modified except that the 

 lower ends of the inner cells appear to be destroyed, and that 

 here and there several cells of both rows are destroyed to make 

 room for a mass of light-colored, stromatic hyphae to connect the 



1 Specimens of this species are in the collection of the New York Botanical 

 Garden under the manuscript name of Ophiodothis Fici Earle. The species 

 has also been collected in Cuba. 



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