254 



THAXTER. MONOGRAPH OF THE LABOULBENIACE^E. 



nary extra Asiatic type has not enabled me to detect any difference that seems essential. Figs. 16-17 

 represent the forms which have been taken as the types of this species. 



Dichomyces Madagascarensis Thaxter. Plate XXXII, figs. 11-13. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 424. April, 1900. 



Basal cell deeply suffused with brown. Lower tier very long and slender, opaque except for a faint 

 median translucent line: middle tier with three to five of the median cells distinguishable, red-brown; 

 the rest indistinguishable in the opaque margins which extend upward to form long fork-like outgrowths 

 on either side that may reach nearly to the tips of the perithecia; antheridia not large, brownish: upper 

 tier consisting of about twenty-one to twenty-three cells, tinged with reddish brown, relatively large, 

 deeply concave distally; the median cells like those of the middle tier, marked by fine faint transverse 

 strire, bearing normally two perithecia which are long and slender, often slightly curved and divergent, 

 pale reddish brown, the tip narrow, the posterior lip-cells forming two small, slightly divergent projec- 

 tions or auricles curved at the tips, the anterior lips meeting in a point between them. Appendages hya- 

 line, sometimes equalling the perithecia in length. Spores very slender and abundant, 35 X 2 p.. Peri- 

 thecia 125-135 X 25 /£. Total length to tip of perithecium 320-350 /i. Receptacle 225-240 X 105 fi. 



On abdomen of Philonthus Sikorae Fauv., Paris Museum, No. 179, Tananarivo, Madagascar. 



This is a large and well marked species, most nearly related to D. hybridus. It does not appear, 

 however, to be dimorphic. The perithecia are never more than two, although the distal tier is unusually 

 well developed, and are further more elongate with more slender auricles. 



Dichomyces biformis Thaxter. Plate XXXIII, figs. 1-5. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 422. April, 1900. 



Basal cell hyaline or nearly so, usually somewhat enlarged and often with a heel-like anterior pro- 

 jection ; lower tier rather narrow, quite opaque, the marginal cells extending up to the subterminal margi- 

 nal cell of the middle tier or to the cell next below it: the middle tier short and stout, the nine to eleven 

 cells hyaline or faintly reddish brown above, usually becoming more or less suffused below and externally 

 with brown; the median cells, wdiere suffused, marked by darker transverse flecks on their anterior faces, 

 the marginal cells ending in a blunt distal often hyaline prominence on either side; antheridia short and 

 stout subconical, subtended by a single brown inconspicuous appendage: the distal tier assuming in 

 well developed individuals the form of a rather slender crescent, the number of cells very variable, the 

 maximum about fifty, sometimes less than half this number, in which case the form is stouter, the margi- 

 nal cells rarely extending above the tips of the perithecia, which are four to eight in number and of two 

 kinds which are not known to be associated on the same individual; in the one case they are stouter, 

 purplish brown, the basal third, or more, often abruptly hyaline or nearly so, the much darker red brown 

 tip tapering rather abruptly to the apex, which is hyaline, nearly truncate, with a well defined median 

 blunt projection; the posterior hp-cells prolonged, much as in D. insignis, to form a long horizontal nearly 

 cylindrical, or slightly tapering, bluntly tipped hyaline appendage on either side; the second type more 

 often longer and more slender than the first, pale reddish brown, the tip tapering, slightly truncate or blunt, 

 often with a blunt median projection as in the first type, but without appendages. Perithecia 105-110 X 

 20-35 ft. Receptacle 200 X 100-300 X 270 /x. 



On Philonthus sp., Niagara Falls, New York, Mr. Charles Bullard: on Philonthus umbratilis Grav., 

 British Museum, No. 362, Leicester, England; Paris Museum No. 206 and British Museum, No. 407, 

 Madeira; Paris Museum, No. 175, St. Pierre et Miquelon: Scotland, Sharp Collection, No. 1213. 



This species has been found by me repeatedly at Fresh Pond on Philonthus umbratilis and in every 

 case the two forms have been associated. It is perhaps the most remarkable and striking species of the 

 genus not only from its dimorphism and the highly developed auricles, but from the extraordinary devel- 

 opment of the distal tier which, in one specimen observed, bore eight fully developed perithecia although 

 four or six are most frequently present. I have seen no instances in which the two types of perithecia 



