412 



THAXTER. MONOGRAPH OF THE LABOULBENIACEJE. 



Laboulbenia melanopus Thaxter. Plate LXVI, figs. 4-5. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 187. Dec, 1899. 



Perithecium free except at the base, large, rather deeply suffused with smoky brown, translucent, 

 not contrasting; the subdistal wall-cells lighter, tapering abruptly to the narrow somewhat incurved tip, 

 the inner lip-cells, only, deeply blackened. Receptacle somewhat curved, tapering below to the short 

 slender basal cell which is smoky black except at its base, the distal cells gradually suffused with yellowish 

 brown. Insertion-cell unmodified, blackened externally, the basal cells of the outer appendage becoming 

 blackened externally very broad and short, bearing distally a series of erect branches at first more or less 

 double, but later multiplied to form a dense tuft covering the expanded upper surface of the cell; the 

 basal cell of the inner appendage producing similar but smaller groups of branches on either side, the 

 basal cells of all the branches becoming more or less inflated distally, ami bearing terminally and sub- 

 terminally several (six to ten) branchlets, each of which may become again branched, the branches and 

 branchlets distinguished by blackened septa; the ultimate branchlets very slender flexuous hyaline, not 

 extending to the tip of the perithecium in the types. Spores about 60 X 4.5 fi. Perithecium 290 X 70 fi. 

 Total length to tip of perithecium G75 /<; to insertion-cell 400 //. Appendages, longer 140 ,«. 



On a carabid (allied to Harpalusf), at the tip of abdomen. Paris Mus. No. 115, Africa. 



This very distinct species is most nearly allied to L. variabilis and L. oriental is, from which it is, 

 however, so distinct that its numerous differences do not need to be pointed out. The material is unfortu- 

 nately not abundant, and the mature individuals have their appendages more or less broken in all cases; 

 but the manner in which they originate is clearly seen in fig. 5, a young individual in which neither the 

 basal cells of the inner appendage nor of the branches have begun to proliferate. 



Laboulbenia Gyrinidarum Thaxter. 



The type of this species was figured (Plate XXII, fig. 31) in my Monograph, but a more careful 

 reexamination of the material available shows that there are two species often associated on our American 

 Gyrini. The type is distinguished by its smaller size, its straight, almost isodiametric, perithecium, 

 which is furnished with short blunt projections as in the figure; and by the narrower insertion-region, 

 and less abundant appendages: the wall-cells of the perithecium are straight, and the receptacle usually 

 geniculate. The second form corresponds so closely to that which I have described as L. chatophora, 

 of which a single example was found in the Sharp Collection on Dineutes soJitarivs from Madagascar (?) 

 that I am unable to distinguish them specifically; and this species should therefore be added to the North 

 American forms. It is the tip of the perithecium of this second form that is represented in fig. 37 of my 

 Monograph, the projections from which are much longer and more sharply pointed, usually black and 

 spine-like. The general form of the perithecium is conical, exactly as in L. chaiophora, the wall-cells 

 spirally twisted, the plant as a whole usually straight and subfusiform, the insertion-region much broader 

 than in L. Gyrinidarum , and the appendages more numerous. 



Several specimens in very poor condition have been obtained from British and Italian species of Gyri- 

 nus (British Museum No. 459 on Gyrinus urinator Illig., British Isles, and in the Florence Museum on G. 

 tricolor Payk. and G. striatus Fabr., Italy, which have been referred provisionally to L. Gyrinidarum. 

 It is uncertain, however, whether they properly belong to this species. Several poor specimens on Gyrinus 

 from Mexico and from South America have also been examined, but here also the material is not sufficient 

 to render a reliable determination possible, and their reference here is only provisional. 



Laboulbenia ch.etophora Thaxter. Plate LXVII, fig. 19. 

 Proc. Am. Acad. Arts and Sci., Vol. XLI, p. 317. July, 1905. 

 Perithecium dirty olive brown, straight, subcorneal; the upper two-thirds free, tapering from a broad 

 base, the wall-cells with a distinct spiral twist, very slightly enlarged below the tip, which is slightly, but 

 rather abruptly, distinguished, symmetrical, black, except distally; the apex rounded, and bearing an 

 erect shorter, and an externally divergent, much longer, straight, black-brown, spine-like process. Re- 



