428 



THAXTER. MONOGRAPH OF THE LABOULBENIACE^J. 



arise singly or opposite in pairs, or in whorls of three or four from the distal (one to four) cells of the 

 appendage. Perithecium solitary, sessile at the tips of the primary and secondary axes, often straight 

 and symmetrical tapering to the truncate unmodified apex, pale becoming amber-brown. Spores about 

 38 X 3 ;l. Perithecia 100-150 X 25-40 //. Sterile appendages, longer 100 X 7 j«. Greatest length to 

 tip of perithecium (main axis) 300-400 X 35 ;t. 



On inferior surface of thorax of Pinophilus sp. indet., British Museum, No. 390, Burmah, India. 



In the individual figured, the basal and subbasal cells are abnormally placed or the latter is abnor- 

 mally septate. In the other specimens these two cells are directly superposed. The species shows a good 

 deal of variation in the number of cells composing both the main and secondary axes, and also in the 

 number and position of the latter. 



COMPSOMYCES Thaxter. 



This genus and Moschomyces, which may prove to be not generieally separable from it, are decidedly 

 isolated, and it is difficult even to suggest the probable affinities of the few species thus far discovered. 

 It seems to me that it is better to regard the perithecia as arising from a single stalk-cell which is in turn 

 borne on an appendiculate branch from the receptacle consisting of a single cell. The sterile appendages, 

 or certain of them, are peculiar in having slightly oblique septa when young, and it is only in this group 

 that asci with eight spores are definitely known to occur. 



Compsomyces Lestevi Thaxter. Plate XLIII, figs. 9-12. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXV, p. 439. April, 1900. 



Receptacle consisting of a small basal and subbasal cell, the latter giving rise to rarely more than two 

 branches; one of which consists of a basal cell, from the upper side of which the stalk-cell of the perithe- 

 cium arises ; while externally it gives rise to a characteristic sterile branch, simple, usually slightly upcurved, 

 rather closely and somewhat obliquely septate, commonly consisting of about nine superposed cells, taper- 

 ing rather abruptly at the tip. Perithecium borne on a well developed erect stalk-cell, nearly symmetri- 

 cal, tapering from about the middle to the broad truncate undifferentiated tip; the basal cells small, but 

 slightly distinguished from the inflated base of the ascigerous portion, the spores few and relatively large. 

 The other branch arising from the subbasal cell of the receptacle, an antheridial branch, divergent, con- 

 sisting typically of four superposed cells above which it becomes furcate, dividing into two branches which 

 are large stout tapering, distally curved; the third cell of the appendage producing a single short flask- 

 shaped antheridium distally on its inner side and sometimes giving rise to a branch similar to those above. 

 Spores 42 X 4 /i. Perithecia 75-85 X 30-35 /x, the stalk 75 X 22 /i. Antheridial appendage including 

 branches 275 /i, the basal part about GO X 20 ji. 



On abdomen and elytra of Lesteva sicula Erich, British Museum, Nos. 452 and 453, Paisley and Red 

 Hill, England: on L. pubescens Mannerh., No. 1094, Scotland: on Lesteva sp. No. 1175. Savoy, in 

 Sharp Coll. 



This species differs from the type of the genus in having a single antheridium definitely placed on a 

 main appendage; at least this appears to be the condition in all the specimens examined which have 

 been in sufficiently good condition to show the antheridium at all. At first sight it might seem wholly 

 different from C. verticillafus from the apparent absence of a basal appendiculate cell below the stalk-cell 

 of its perithecium; but an examination of young specimens shows, as in fig. 12, that this appendiculate 

 cell is present, although very small, and as the individual matures the enlargement of the stalk-cell, as 

 well as of the basal cells of the other appendages, causes it to become obscured and displaced, so that the 

 stalk-cell itself appears to arise directly from the subbasal cell of the receptacle. That this is not the 

 case is clearly seen in the figure mentioned, which also shows the position of the single antheridium. 

 The material from Dr. Sharpe's collection is in somewhat better condition than the types, but does not 

 vary greatly. The specimens from Scotland have more slender perithecia, but do not seem otherwise 

 different. 



