I 
MONOGRAril OF THE LABOULBENIACE.i:. 285 
than any of its allies. I have met with it on one occasion only, when several hosts were 
collected from a licap of rubbish near cultivated land, on which the jKirasite occurred in great 
numbers, thickly covering the lower surface of the abdomen and extending to the legs and 
thorax. Unfortunately, all but one of these hosts made their escape In transit, but llic sin<*;lc 
one remaining has furnished abundant material of the mature form. Owing to its light color, 
large size, and more than usuall}' divergent, though not erect, habit of growth, it is not readily 
overlooked on the black abdomen of its host. 
CIIITONOMYCES Peyritsch, Plates VIII and XXYL 
Sitz. d. k. Acad. d. Wiss. LXVIII, p. 250 (1873) ; Rktmatomvces rETnirscii, 1. c. p. 251 ; llKiMATOMvcr^ tmexp., Thaxter. 
Troc. Am. Acad. Arts and Sci. Vol XXVJl, p. 30. 
Receptacle consisting of a basal and a terminal portion; the former consisting of two 
superposed cells, and tliree or four upper smaller cellb which form the base of the pcrithecinm; 
the latter consisting of four cells lying beside the pcrithecinm, the terminal cell always free, 
originally more or less dome- or bell-shaped, bearing a sin^j-le terminal (ipj)endage, and sometimes 
becominfz; otherwise modified at maturitv; the sub-terminal cell connected on its inn*'T side will), 
or rarely free from, the two cells below it, from tlie upper of which is separaied a snudl c(dl 
that bears terminally, in the angle formed by the pcrithecinm and the receptacle, one or iwo 
appendages, beside which is situated the usually small antheridium (?). Appendages slender, 
filamentous, simple, aseptate or spuriously septate, hyaline, evanescent, the base blackened and 
slightly constricted, Perithecium more or less completely united to the distal portion of the 
receptacle, each series of wall-cells containing not more than six cells, some of which may be 
appendiculate ; the apex often variously modified. Spores fusiform, onct septate. 
Since the description of numerous species under the name lleimatomyccs, I have had an 
opportunity of examining specimens of Chitonomyces melanurus Peyritsch, and, as I formerly 
suggested, the two genera prove identical. I liave therefore concluded to use the latter name to 
distinguish the genus ; since, although I very much dislike to regard the rules of priority at the 
expense of those of common sense, it seems desirable that the nomenclature adopted in the 
present monograph should be, in so far as possible, a fixed one, and the name Chitonomyces 
undoubtedly has precedence in the present instance to the extent of nearly half a page. 
The genus is one the position of which has been, until the present paper was in press, quite 
uncertain ; the character of the sexual organs not having been ascertained with suflicicnt exact- 
ness to warrant any definite statement concerning them. The very recent discovery, however, 
of an undescribed and very closely allied aquatic genus, in which the antheridium is so placed 
that it can be readily seen, renders its position no longer doubtful, and confirms my first impres- 
sion, which was based on the general resemblance of its appendages and the structure of its 
receptacle to those of Peyritschiella. The new genus, a description of which is necessarily 
reserved for a succeeding supplement, is characterized by a general structure curiously inter- 
mediate between that of Chitonomyces and the genus last mentioned, the small but very definite 
compound antheridium occupying a position on the anterior margin of the plant just below the 
base of the perithecium. 
