298 



THAXTER. 



MONOGRAPH OF THE LABOULBENIACE7E. 



Acompsomyces Corticarle Thaxter. Plate XLII, fig. 5. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXVII, p. 37. June. 1901. 

 Receptacle narrow below, distally enlarged, hyaline; the subbasal cell small. Basal cell of the 

 appendage brown, distally narrowed to the base of the appendage proper, which is brown, and consists 

 of three symmetrical cells, the upper smaller, bearing a terminal antheridium, the lower bearing several 

 antheridia somewhat irregularly. Perithecium brown, rather abruptly distinguished from the short hya- 

 line stalk; the tip very broad and darker; the lip-cells forming four hyaline-tipped, nearly symmetrical 

 papillae which terminate four corresponding ridges. Spores about 30 X 2 ft. Perithecia 90 X 2G ft, the 

 stalk 15 ft. Receptacle 25 ft. Antheridia! appendage, above stalk-cell, and including terminal antheri- 

 dium, 40 ft. 



On elytron of Corticaria sp. Berkeley, California. 



This species is well distinguished by its color and form and especially the conformation of the tip 

 of the perithecium. The unique type was found on a small Corticaria in a lot of small flies collected 

 by sweeping near Berkeley. 



Acompsomyces brunneolus Thaxter. • Plate XLII, figs. 10-12. 

 Proc. Am. Acad. Arts and Sci., Vol. XLI, p. 311. July, 1905. 



Colorless, the tip of the perithecium and its posterior margin suffused with brown, the suffusion ex- 

 tending to the base of and including the appendage. Receptacle short, the basal cell hyaline, relatively 

 large, slightly inflated above, tapering to the small foot ; the subbasal cell very small, twice as broad as 

 long; the basal cell of the appendage deeply suffused with blackish brown, especially externally; relatively 

 small and short, the rest of the appendage much as in the other species, somewhat narrow and suffused 

 with brown. Stalk-cell of the perithecium short, slightly longer than broad, the perithecium relatively 

 large and stout, nearly straight, the inner margin nearly straight, and suffused with brown, the outer bent 

 abruptly inward below the tip, which is brown, short, stout, well differentiated, broadly truncate; the lip- 

 cells rising in a truncate conical apiculus subtended by the four clearly distinguished broad subtcrminal 

 wall-cells. Total length to tip of perithecium 125 ft. Perithecium 80 X 20 ft, the stalk-cell 12 X 10 ft. 

 Receptacle 28 X 12 ft. Appendage to tip of spine 45 X 10 ft, the basal cell 10 ft long. 



Near the base of the right elytron of Corticaria sp., Kittery Point, Maine. 



Several specimens of this pretty species were found on a single host on Cutts Island, but although 

 diligent search was made no further material has been obtained. 



Acompsomyces pauperculus Thaxter. Plate XLII, figs. 13-15. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXVIII, p. 23. June, 1902. 

 Hyaline or nearly so. Receptacle short, somewhat bent; the distal cell very small, irregular, sharply 

 pointed below, externally separated from the basal cell by an oblique septum; the basal cell three or 

 four times as large, narrow below, expanded above its distal point, forming a right angle, the septum on 

 one side applied to the base of the stalk-cell of the appendage. The latter subtriangular, its lower half 

 in contact on the inner side with the two cells of the receptacle, its upper with the stalk-cell of the peri- 

 thecium; the rest of the appendage free, relatively large, hardly inflated, its lower cell about as large as 

 the two upper combined and bearing commonly one, sometimes three, antheridia as in A. Atomariw; 

 the two cells above it nearly equal or the upper often smaller and bearing its antheridium subterminally, 

 so that the spinous process of the latter appears to terminate the appendage, the wall distinguishing this 

 antheridium being commonly invisible from its obliquity. Stalk-cell of the perithecium about as large 

 as that of the appendage and similarly shaped, except that its position is reversed, separated distally 

 from the basal cells of the perithecium by a very oblique septum: the body of the perithecium short, 

 stout, bent asymmetrically, and considerably inflated; the inner margin straighter, the short squarish 

 tip rather abruptly distinguished, the apex subtended by four distinct symmetrical prominences, which 

 form a crown surrounding the four appressed prolongations of the lip-cells, which appear as a blunt, 



