276 



THAXTER. 



MONOGRAPH OF THE LABOULBENIACEiE. 



be most reliable in distinguishing species are found in the antheridium. The number of rows of antheri- 

 dial cells, and the number of cells in each row, are apparently very constant; variations in these respects, 

 in a given species, occurring rather exceptionally. In some forms the antheridium may be the most 

 complicated male organ that occurs in the whole group, with the exception of that in Eumonoicomyces 

 and possibly in some forms of Haplomyces; since, as in E. Catoscopi, there maybe over fifty antheridial 

 cells in a single antheridium. In certain other species, nevertheless, this number may be reduced one 

 half or more, as in E. Euprocii or E. -spinosus. 



The structure of the antheridium appears to correspond in general to that of most of the other com- 

 pound types. The antheridial cells are obliquely disposed in rows, usually three, more rarely four or 

 even five, on either side; and their bases being external, they empty by short necks into an interior cavity, 

 which connects directly with an efferent tube, through which the antherozoids are discharged in large 

 numbers. The structure is closely comparable with that of Haplomyces, in which, however, the an- 

 theridia, not being separated by a sterile external marginal cell, surround the antheridial cavity com- 

 pletely. 



An examination of Plate XXXVIII will show that there is a monotonous sameness among the species, 

 which renders a very careful comparison of characters necessary in order to distinguish them. It should 

 be noted that the spores, in many of the species at least, are peculiar in possessing a bluntly rounded apex, 

 in place of the usual acuminate tip. The inner lip-cell is in general more or less distinctly modified, 

 usually also more deeply colored, forming in many instances a more or less characteristic rounded promi- 

 nence, as in figs. 28 and 36. The characteristic spine which persists in some species at the tip of the 

 antheridium (Figs. 10 and 19) represents the apex of the spore, and is primarily terminal, as in Stig- 

 mafomyces, where it is almost invariably present. The ascogenic cells may be somewhat peculiar and in 

 some species numerous. In E. Catascopi, for example, as is indicated at the base of the perithecium 

 in fig. 13, they are long erect subclavate and at least eight in number; while in some of the smaller species 

 there do not appear to be more than four, or possibly two, in some cases. The species appear to be very 

 generally distributed and the hosts are in all instances beetles belonging to the Carabidse. 



Eucantharomyces spinosus Thaxter. Plate XXXVIII, figs. 17-20. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 416. April, 1900. 



Perithecium straw-colored, rather stout, inflated, tapering to the broad asymmetrical tip which is 

 slightly sulcate; the outer lips often larger than the inner, the latter more deeply colored and not very 

 conspicuous; the stalk-cell rather short. Receptacle short, the cells nearly equal. Appendage much 

 as in E. DiapJiori, more slender, the marginal cell extending nearly to the base of the subbasal cell, dis- 

 tinctly enlarged below a terminal spine-like process, which is usually nearly erect; the antheridial cells 

 in three rows of five, three (relatively large) and one to two cells respectively, the discharge tube large 

 and broad, nearly truncate, bent abruptly upward from the base. Spores 35-40 X 3.5-4 fi. Perithecia 

 138 X 41 ji. Appendage 70 X 14 /x, the antheridium 35 X 10 p. Receptacle 50 X 20 y.. Total length 

 to tip of perithecium 190-207 y. 



On elytron of Drypta sp., Paris Museum, No. 80. Java. On Drypta lineola Dej., Hong Kong; 

 Berlin Museum, No. 950. 



The antheridium in this species is perhaps the simplest thus far observed in the genus, the cells of 

 the third row being apparently functionless and variable in form and number (one to three). The termi- 

 nal spine stouter and larger, as a rule, even than that of E. Diaphori, the antheridium of which is other- 

 wise very different. From its small size and pale color it is distinguished only with the greatest difficulty 

 on the elytra of its host when dry. 



