468 PROCEEDINGS OP THE AMERICAN ACADEMY. 



RHACHOMYCES nov. nom. = ACANTHOMYCES Thaxter. 



Rhacuomyces speluncalis, nov. sp. • 



Perithecium more or less deeply suffused with brown ; short and 

 stout, with a broad bluntly rounded apex. Receptacle slender, the 

 main axis constricted strongly at the septa, its cells rather small, the 

 basal slender and cylindrical ; the remainder, about nine in number, 

 all evenly and rather deeply suffused with brown, and more or less 

 uniform in size. Appendages mostly opaque, more or less rigid, 

 hyaline-tipped, those surrounding the base of the perithecium hardly 

 equalling it in length, a few lower on the receptacle exceeding its 

 apex by the whole length of the plant : of the shorter median appen- 

 dages some are terminated by a peculiarly modified partly hyaline 

 (antheridial ?) cell, the neck-like tip of which curves strongly out- 

 wards, terminating bluntly. Perithecia 90 X 37 fx. Receptacle about 

 110 /A (when not proliferous). Longest appendages 300 /a. Total 

 length to tip of perithecium 185 fx to 260 /x (in proliferous forms). 



On Anophthalmus jnisio Horn. West Virginia. 



The smallest species of the genus, more nearly allied to R. lasio- 

 phorus in the form of its perithecium and the disposition of its appen- 

 dages around the base of the latter. It is quite distinct, however, 

 from any of the described species. 



DIPLOMYCES, nov. gen. 



Flattened antero-posteriorly, sub-triangular, bilaterally symmetrical, 

 furcate through the presence of a pair of prominent posterior projec- 

 tions. The receptacle consisting of two superposed cells, followed by 

 four cells placed antero-posteriorly in pairs, of which the posterior 

 produce the characteristic prominences ; the anterior a pair of short 

 stalked perithecia, near the base of which, within and above, arise two 

 or more pairs of appendages, and eventually a second pair of peri- 

 thecia. Appendages copiously branched, many of the branchlets ter- 

 minated by beak-like cells. Spores once-septate. 



A singular genus, recalling Teratomyces, to which it seems most' 

 nearly allied through the presence of the characteristic terminal beak- 

 like cells of its appendages. The branching of the latter is not, how- 

 ever, sympodial in a single plane, as is the case in Teratomyces, and 

 the general structure of the receptacle is difficult to homologize with 

 that of any other genus. The second pair of perithecia arise in all 

 probability from secondary divisions of the pair of perithecia-bearing 



