324 



MONOGRAPH OF THE LABOULBENIACEyE. 



antheridia terminally or laterally. Receptacle long and slender, but slightly expanded distally, 

 the large basal and sub-basal cells forming a sub-cylindrical stalk. Spores, 46 x 7 fi. Peri- 

 thecia, 110-125 X 50 /x. Appendages (longest), 425 p. Total length to tip of perithecium, 

 300-330 /*. 



On Anisodactylus nigerrimus Dej., Cambridge, Mass. 



This graceful species was at first taken for a variety of L. clegans ; yet it seems so constant 

 in its differences that I have concluded to distinguish it as a separate species, the structure of 

 the tips of its perithecium (fig. 8) being its most essential character. Its slender, flexuous 

 appendages, from their form as well as from their mode of branching, also serve as a means of 

 distinguishing it, and seem to vary but slightly from the type represented in the figure. Its 

 position on the host is, singularly enough, exactly the same as that occupied by its near ally, 

 L. elegans. It has been found in a single locality only, near the margin of Fresh Pond, where a 

 dozen or more infested hosts have been from time to time obtained. 



Laboulbenia elegans Thaxter. Plate XIV, figs. 3-6. 



Proc. Am. Acad. Arts and Sci. Vol. XXIV, p. 13. 



Hyaline, becoming finally more or less tinged with yellowish brown. Perithecium more or 

 less inflated, abruptly constricted below the deep black apex, the lip-cells very prominent, bent 

 strongly outward from a rounded inner jet-black prominence to the hyaline tips, mouth-like 

 about the pore. Outer appendage arising from a rather large basal cell, above which it produces 

 two branches, the outer simple, rigid, divergent, tapering, the inner producing from its basal cell 

 two branches symmetrically divergent, long, rigid, simple, and tapering : the inner appendage 

 arising from a small basal cell, which produces usually a single branch on either side which may 

 be several times irregularly branched, the branchlets fertile, bearing a few antheridia, singly or 

 in pairs or sterile, often falcate, peculiarly inflated toward the middle and constricted at the 

 septa. Receptacle but slightly expanded distally, the sub-basal cell stouter than the basal, the 

 two usually somewhat inflated and suffused in the region of their common septum. Spores, 

 40-50 X 4-5 ft. Perithecia, 110-150 X 50-65 ft. Appendages, longer, 250-400 ft ; inner, 50-75 ft. 

 Total length to tip of perithecium, 290 ft (larger, 335 ft). 



On Harpalus pennsylvanicus DeG., New England. 



A common and very pretty species, though more stiff and less graceful in its habit than the 

 preceding. It is one of the few forms in which the branching of the outer appendage is almost, 

 though not absolutely, invariable. It is at first perfectly colorless, becoming brownish only in 

 very old individuals, and is very constant in form. It is confined to the lateral face of the pro- 

 thorax of its host on the right side, where it forms a rather compact tuft just below the project- 

 ing margin ; but very rarely it occurs, sometimes in company with L. conferta, on the 

 corresponding left side, and has been once noticed on the anterior legs. The host is very com- 

 mon, and may be found in late August and early September, devouring the pollen of the common 

 rag weed (Ambrosia artemisicefolia') in open fields. 



