304 



THAXTER. MONOGRAPH OF THE LA BOULBENI ACEjE. 



curved or sometimes straight, nearly cylindrical or slightly tapering; the tip slightly but abruptly narrower, 

 relatively short, somewhat asymmetrical; the apex nearly symmetrical, four papillae being arranged 

 about a somewhat more prominent central projection. Appendage rather short and stout, distinctly 

 broadened in the middle, the stalk-cell, stout, the basal cell half as large, or less, and fertile; the series 

 of six to eight fertile cells above it surmounted by a single usually sterile antheridium, and distinguished 

 by slight successive constrictions, broad and much flattened, each bearing a single antheridium, the fifth 

 furnished with a very sharp spine; the antheridia forming a usually lateral series, their necks becoming 

 strongly curved. Receptacle elongate, slender, becoming brownish or yellowish, the upper cell often more 

 than twice as long as the basal. Spores 25 X 2.5 fi. Perithecium: venter 90-165 X 35-47 /<; neck 

 90-160 X 17 {i (the tip 25-30 /*). Appendage 40-50 p., the stalk-cell 15 ;i. Receptacle 100-250 X 15 /u 

 Total length to tip of perithecium 350-600 // (average 500-550 /«)• 



On Hijdrina sp., Kittery Point, Maine. Usually on the upper surface of the thorax, less often on the 

 legs and elsewhere. 



This well marked species was obtained on a small fly collected by sweeping the flowers of Yarrow 

 (Achillea) on Cutts Island in late August. It is conspicuous from its large size and dark brown perithe- 

 cium, and may readily be seen with the naked eye when growing in its usual position on the thorax. It 

 is distinguished by the clean cut wing-like ridges which run spirally between the wall-cells and end abruptly 

 in an enlargement at the base of the neck. In this respect it resembles S. purpureus, in which the ridges 

 are, however, nodulose when well developed, as well as in the uniseriate arrangement of its antheridia; 

 but is in other respects quite different. The spiniferous cell is not converted into an antheridium, but is 

 subterminal; the appendage being proliferous beyond it. 



Stigmatomyces Venezuela Thaxter. Plate XLIX, figs. 20-21. 

 Proc. Am. Acad. Arts and Sci., Vol. XLI, p. 314. July, 1905. 



Perithecium slender, curved throughout, the venter pale amber-brown, hyaline externally, not dis- 

 tinguished from the neck on the inner side; the outer wall-cells bulging more or less conspicuously; the 

 neck tapering slightly, the tip blunt, and unmodified; the basal and stalk-cells hyaline, distinguished 

 from the venter by an abrupt external constriction. Cells of the receptacle hyaline, subequal, the basal 

 bulging distally, below the subbasal, to which it is thus asymmetrically adjusted. Stalk-cell of the append- 

 age tinged with amber-brown, more than twice as long as broad, abruptly distinguished from the lower 

 part of the basal cell, which is small and brown : the appendage proper small, hyaline, withering at matur- 

 ity, except the lower part of the basal cell; consisting apparently of about three cells producing about 

 four nearly free antheridia. Perithecia 95 X 30 fi. Receptacle 90 X 14 /z. Appendage 45 ft, exclusive 

 of stalk-cell, which is 22 \i long. 



Growing at tip of abdomen of Limosina sp., Island of Margarita, Venezuela; Dr. A. F. Blakeslee. 



Although not striking in its appearance, this species seems well distinguished from all other forms of 

 Stigmatomyces, owing to the peculiar relation between the basal and subbasal cells of the receptacle, as 

 well as by the form of its perithecium. Eight mature individuals have been examined, which show little 

 variation; but in none of them is the antheridial appendage sufficiently well preserved to admit of its 

 being figured in detail, the whole functional portion apparently becoming shriveled and the antheridia 

 ceasing to function at an early stage in the maturity of the individual. In one example it seems as if the 

 lower antheridia, only, had been functional, and the upper were replaced by sterile rounded cells. 



Stigmatomyces Diopsis Thaxter. Plate XLIX, figs. 8-10. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXVI, p. 399. March, 1901. 



Colorless or slightly yellowish. Venter of the perithecium long-oval or elliptical, pale reddish amber, 

 rather abruptly distinguished from the paler neck, which tapers but slightly, except at its base, is straight 

 or slightly bent, and traversed by four broad longitudinal ridges which are corrugated by about jsix succes- 

 sive elevations and depressions; a seventh distal elevation, larger and more prominent than the rest, is 



