220 



MONOGRAPH OF THE LABOULBENIACEiE. 



different specimens, but is usually not greater than is represented in fig. 15 (I r) 

 and in fig. 16. Before fertilization it can be clearly seen, as in the last-inentioned 

 figure, that the trichogyne and the basal cell (c) constitute a single cell, and the 

 nucleus is usually readily made out in the position indicated at the base of the 

 trichogyne. Meantime the cells [n n) and (o d) of fig. 13 have increased in size, and 

 the former have begun to grow up still further around the base of cell (e), fig. 13, (e"), 

 fig. 14. 



With the maturity of the trichogyne the female organ has completed its develop- 

 ment, and we have the condition represented in fig. 15, from which it will be seen that 

 the latter, which may be conveniently termed the procarpe, consists of three distinct 

 parts, which, so far as is known, are present in all genera of Laboulbeniaceae. Of 

 these the uppermost may be properly called the trichogyne, and in the present illustra- 

 tion is unicellular, though often, as will be seen presently, far more complicated in 

 structure ; the middle portion in this, as in all other instances, also unicellular, which 

 we may call the trichophoric cell [e"), and the lowest portion (/), which may be termed 

 the carpogenic cell, being that portion of the procarpe which is fertilized, and the only 

 part which persists and undergoes further development. As is shown in the figure, 

 the carpogenic cell is completely surrounded by eight cells, four of which (oo) lie be- 

 low and around it, and, remaining undivided, form the basal cells of the mature 

 perithecium ; while the four others (n n) completely surrounded it, and, as will be seen 

 later, form by further division the wall- and lip-cells of the perithecium. These 

 eight cells are arranged in four longitudinal rows, and, in the stage represented, the 

 upper four have already begun to grow up around the trichophoric cell, the lower 

 half of which is now enclosed by their advancing tips. In the stage represented in 

 fig. 15, the antherozoids, which have been continuously escaping from the antheridia 

 since the stage represented in fig. 7 was reached, begin to adhere to the trichogyne, 

 often in larger numbers than are represented in the figure, and fertilization is accom- 

 plished, probably with considerable rapidity if one may judge from the rarity of 

 conditions which are intermediate between that represented in fig. 15 and that shown 

 in fig. 19, where the trichogyne has entirely disappeared. In the comparatively in- 

 frequent instances in which one finds an adherent trichogyne belonging to a procarpe 

 in which fertilization has evidently been accomplished, slight elevations may be seen 

 which coincide with the position of usually more than one of the antherozoids (figs. 17 

 and 18). In such cases, although it is very difficult to determine the actual presence 

 of conjugation in the case used for illustration, it is evident that a wall has been 

 formed around the antherozoid, which often seems inflated and nearly empty of 

 contents. 



