246 Transactions British Mycological Society. 
(4) The smaller conidia with exosporic emergences, less pro- 
minent, however, than in the type species. 
The present form, which I call Sigmoideomyces divaricatus, is 
notably more closely allied to Thaxter’s American species than 
to the Birmingham one. 
Mrs Bayliss Elliott raised the interesting question whether 
Sigmoideomyces was congeneric with Gymnoascus. The resem- 
blance of these masses of fertile hyphae to the perithecia of 
that genus is certainly striking but the conidial and ascigerous 
forms have not been found in conjunction and the matter is 
still open. It must be admitted, however, that the Birmingham 
species, S. clathroides, is more like Gymnoascus than are either 
S. dispiroides or S. divaricatus. 
SIGMOIDEOMYCES Thaxter, emend. 
Fertile hyphae septate, loosely aggregated and either bent 
into many sigmoid curves or radiating from a common centre; 
branching sub-dichotomous, the ultimate branches sterile. 
Conidiophores vescicular, spherical, borne laterally on the 
hyphae by a stalk. Sterigmata short, spine-like, scattered. 
Conidia one-celled, spherical, echinulate or almost hyaline. 
S. divaricatus n.sp. Fertile hyphae forming buff-coloured tufts 
_ about I mm. in diameter and 2-3 mm. apart; the hyphae rigid, 
radiating from a common centre, tapering, the ultimate branches 
freely divaricating and bearing laterally small, conical protru- 
berances. The cells at the angles of dichotomy, in the inner part 
of the tuft, bear each two short, cylindrical outgrowths, in a 
plane at right angles to that of the branching, each terminating 
in a thin-walled, spherical conidiophore, 20 (15-25) in dia- 
meter, upon which are borne the conidia 6-9 », minutely echinu- 
late, hyaline. Sterile hyphae forming a scanty mycelium, each 
being about 2-3, in diameter. 
On surface of soil in pot. Greenhouse: Botanical department: 
University College, Cardiff. 
REFERENCES. 
THAXTER, R.—On certain new and peculiar North American Hyphomycetes.... 
Bot Gazette, XVI, p. 14 (1891). 
Bay.iss ELLiott.—Sigmoideomyces clathroides. A new species of fungus. 
Trans. Brit. Mycol. Soc. Iv, p. 121 (1912). 
EXPLANATION OF PLATE XII. 
Fig. 1. Sigmoideomyces divaricatus. A small “‘perithecial” tuft of fertile 
hyphae, teased out, showing the conidiophores, from which the conidia 
are detached. x 200. 
Fig. 2. Portion of an older tuft; the conidiophores having fallen off. x 200. 
Fig. 3. A single sterigmaton. x 2000 ca. 
Fig. 4. Conidia, and a portion of the conidial wall in section, showing the 
minute prominences. Conidia x 750. 
Fig. 5. Fertile hyphae, illustrating the mode of branching and the attachment 
of the conidiophores. x 750. 
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