302 



MONOGRAPH OF THE LABOULBENIACEiE. 



IDIOMYCES Thaxter. Plate IX, figs. 16-21. 



Proc. Am. Acad. Arts and Sci. Vol. XXYIII, p. 162. 



Receptacle consisting of two superposed cells, followed by two cells, an anterior and a pos- 

 terior, — the posterior cell followed by a vertical series of superposed cells bearing externally 

 fertile and sterile appendages in three vertical rows ; the anterior cell producing one or 

 more stalked perithecia and numerous fertile appendages arising from small cells separated 

 from it distally. Perithecia symmetrical with four ascogcnic cells. Fertile appendages con- 

 sisting of a single series of superposed cells, bearing on one side three vertical rows of flask- 

 shaped antheridial cells. Spores once-septate. 



This genus is nearly related to Stigmatomyces, through the structure of its peculiar append- 

 ages, which are very similar, except for the presence of three instead of one row of antheridial 

 cells. Viewed laterally (fig. 18), it is not possible to determine the number of rows ; but a face 

 view, such as is shown in fig. 19, shows the slender necks of the three antheridial cells pro- 

 jecting side by side at regular intervals. The sterile appendages (fig. 20) consist also of a 

 series of superposed cells, each producing a single sterile lateral branch. 



The receptacle is somewhat complicated in structure, consisting of four cells arranged as 

 above described, the peculiarly differentiated posterior series of superposed cells, which bear the 

 appendages externally, recalling, in a way, the primary appendage of Ceratomyces. The cell 

 which produces the perithecia becomes distally divided, usually on one side only, the cells thus 

 formed producing the second set of appendages, which, in Avell developed specimens, may be 

 very numerous and extend almost completely around the base of the stalk-cell of the perithecium 

 on both sides. Fresh material for a more minute examination of this genus is greatly to be 

 desired, since the specimens of the single species which constitute the types are in very poor con- 

 dition, with the exception of the one from which fig. 17 was derived. 



Idiomyces Peyrttschii Thaxter. Plate IX, figs. 16-21. 



Proc. Am. Acad. Arts and Sci. Vol. XXVIII, p. 162. 



More or less tinged with yellowish or amber brown. Receptacle consisting of two super- 

 posed basal cells, surmounted by two cells ; the outer, having a very thick external wall which 

 forms a distinct prominence distally, is succeeded by a row of about five or six superposed, more 

 or less flattened cells, extending beyond the base of the stalk-cell of the perithecium, which 

 bear externally three vertical series of closely-set appendages : the inner is succeeded by a 

 single rounded cell followed by several small cells, which give rise to a series of similar append- 

 ages variable in number. Appendages mostly fertile, borne on one or two squarish basal cells, 

 terminated by a simple or once branched short sterile filament. Perithecia short, thick, sub- 

 conical, the apex sub-truncate, the base inflated, borne on a long stalk made up of a single basal 

 and two sub-basal cells, the outer directly in contact with the perithecium, the inner separated 

 from it by two small cells. Spores, 60 x 4/*. Perithecia, 110-130 x 60-70 /x. Appendages 

 longer, 80 fi. Receptacle, 130-165 x 70-95 /x. Stalk of perithecium, longest, 200 fi. 



On Deleaster dichrous Grav., Germany. 



