368 MONOGRArn of the laboulbeniace^. 
MOSCIIOMYCES Thaxter. Plate XT, figs. 16-18 and 26. 
Proc. Am. Acad. Arts and Sci. Vol. XXIX, p. 97. 
Receptacle composed of a sucter-like compacted mass of pareiichymatous cells penetrating 
the softer cliitin of the host and giving rise above to numerous free cells from the distal ends 
of which are produced solitary stallced perithecia and appendages. Perithecium very large, 
Buh-conical, pointed, the apex symmetrical, borne on two simple superposed stalk-cells followed 
by three small basal cells ; the basal stalk-cell bearing from its distal end a single simple sterile 
appendage. Appendages septate, sparingly branched or simple, the fertile ones stouter, bearing 
the antheridia on short branchlets. Asci sub-cylindrical, eight-spored, arising in great numbers 
and in many rows from a single ascogenic cell. Spores minute, once-septate. 
This genus, although at first sight so remarkably distinguished from all others by its habit 
of penetrating its host and by a cellular base, may yet prove merely a well-marked species' of 
the preceding genus. This suggestion is made on the supposition that an " individual " such 
as is represented by fig. 16 is in reality an aggregation of as many individuals as there arc cells 
in its penetrating base. The spores are discharged in enormous numbers from the perithecium, 
and show a marked tendency to adhere in masses (fig. 18). It is a question, therefore. 
whether the " individual " as figured docs not represent the product of one of these masses and 
not the product of a single spore. Apart from this apparently compound habit, the essential 
characters of the genus are very similar to those of Compsomyces. If this suj)p()sition is 
correct, the sucker-like base is morphologically a compound foot, while llic "numerous free 
cells " above described as rising from it represent the sub-basal cells of the true receptacle. 
Whether the latter has a basal cell distinct from the intruded cells cannot be seen in the speci- 
mens examined. 
The antheridia are flask-shaped cells borne at the tips of short branches, "which arise 
near the ends of the stouter appendages (fig. 26), and arc unlike those of Compsomyces. 
In one specimen, unfortunately destroyed, several trichogynes were observed, which though not 
as luxuriant as is often the case in Compsomyces, were terminated by the same regularly coiled 
spu-al branchlets. As far as can be determined, the asci arise from a single ascogenic centre, 
(parti) 
en 
in very great numbers. The ascus mass is a most remarkal)le object when viewed in fresh 
material under the microscope. What may be called the dorsal view of this mass (represented 
m the second perithecium from the right in fig. 16) shows with great distinctness the round ends 
of a multitude of asci with their contained spores, projecting towards the observer and gradually 
losnig themselves above in the mass of spores, which must be counted in a single perithecium 
almost by thousands. The structure of the perithecium is, like that of Compsomyces, unusual, 
there bemg five transverse series of wall-cells, the lower four marked by singular ridges. 
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