328 



THAXTER. 



MONOGRAPH OF THE LABOTJLBENTACEjE. 



slightly longer than broad, the basal cells forming a hyaline neck bent above the stalk-cell and not dis- 

 tinguished, except in color, from the body of the perithecium, which is nearly straight, symmetrical, dull 

 purplish brown, tapering gradually to the slightly asymmetrical apex; the tip hardly distinguished by a 

 slight external elevation. Stalk-cell of the appendage more or less strongly curved, or recurved so that 

 the appendage bends downward; the insertion-cell slightly broader than long, blackish purple below, 

 separated by a slightly oblique septum from the much larger cell above it, from which four or five branches 

 arise distally; the branches simple, or sparingly branched, hyaline or reddish brown, sterile or bearing 

 antheridia. Perithecia 125-150 X 30-35 /i, the stalk-cell 22-25 Receptacle 200-325 X 25-30 /<. 

 Appendages 185-400 fi. Total length to tip of perithecium 219-490 p. 



On the prothorax of Sclina Westermanni Mostch., India Orient, (labelled "Tranquil"), Berlin 

 Museum, No. 976. 



The only two specimens of this species that were obtained are figured in the accompanying plate. 

 It looks at first sight like a somewhat malformed Laboulbenia, but the essential characters correspond 

 exactly with those of the preceding species. The insertion-cell bears but a single appendage, however, 

 and the host is not penetrated by any rhizoid. The host in this case is a carabid beetle and the genus 

 Selena is said to be synonymous with Ega. 



LABOULBENIA Robin. 



Taken as a whole the characters of this very large and varied genus are remarkably constant as far 

 as the general type of structure and development are concerned, and I have little to add to the account 

 already given in my Monograph. As I have there pointed out the type is peculiar from the fact that the 

 so-called receptacle here, is not homologous with that of its simpler allies, like Rhadinomyces for example, 

 but includes in addition to the primary two-celled receptacle of such forms, a cell series of very constant 

 characters which results from the adnation of the basal portion of a primary appendage with the stalk- 

 cell, and usually with some of the basal cells, of the perithecium. This pseudo-receptacle gives rise, 

 then, to a single perithecium on one side and on the other to appendages which are in reality branches 

 from the adnate primary appendage. The arrangement of cells in this combination is, in general, so 

 regular and constant that it has been found possible and convenient to number the successive cells. The 

 basal and subbasal cells, representing the primary receptacle of the simpler forms, are numbered I and II 

 respectively; the primary appendage includes cells III to V, the latter a double cell which, like cell IV, 

 is normally separated from the "appendages" by a blackened insertion-cell. Of the remaining cells, 

 cell VII corresponds to the normal perithecial stalk-cell of many other genera, which in this instance is 

 never free. 



The more important variations which are met with among the members of the genus are for the 

 most part associated with secondary divisions of the distal portion of the "primary" appendage, that is 

 to say of cells IV- V and of the insertion -cell. Laboulbenia olivacea, for example, is a unique instance 

 in which such a division of cell IV appears to be invariable (Plate LV, fig. 3). In L. Anaplogenii also, 

 although the phenomenon is neither regular nor invariable, the same cell may be divided by one or even 

 more septa, becoming thus to some extent proliferous distally and externally. The most complicated 

 instances of this nature are seen in some of the aquatic species like L. ceraiophora, and such forms might 

 on this account be put in a genus by themselves were it not for the existence of various species showing 

 transitional conditions. 



Normally the free appendages consist of an outer and an inner, arising immediately above the in- 

 sertion-cell from corresponding basal cells; but through the subdivision of these basal cells, as well as of 

 the insertion-cell, the normal arrangement may be wholly confused, as in the instances last mentioned. 

 A further modification which is unusual, is seen in L. proliferans and its varieties (Plate LIII) in which 

 certain secondary cells, resulting from the proliferation of cell V, may give rise to a more or less copious 



