216 



MONOGRAPH OF THE LABOULBENTACEiE. 



The antheridia are usually so placed that the antherozoids are discharged very 

 near to, or even directly upon, the female organ when the latter is mature (Plate I, 

 fig. 15 ; Plate II, fig. 2 ; Plate III, fig. 18). When they are associated with long and 

 well-developed appendages, they are usually borne near the base of the latter (Plate 

 II, fig. 5, anth.), and where also, as in the case of Laboulbenia, there are inner and 

 outer appendages or branches, the male organs usually occur on the inner ones, that 

 is, on those nearest to the female. There are, however, some exceptions to this rule in 

 which the antheridia and trichogynes are not thus closely associated ; as, for example, 

 in Teratomyces, in which the former are borne some distance below the latter, and 

 are curved away from them. In many cases also, though the two sexes may be 

 closely associated, there is often a marked tendency in the male to turn away from 

 rather than towards the female, as in Stigmatomyces and Eucantharomyces. In the 

 dioecious genera, the male and female individuals are always in close proximity, their 

 invariable association resulting from the fact that the spores always become attached 

 to the host in pairs, corresponding to those which are formed in the ascus, and that, 

 of any given spore pair, one member produces a male while the other produces a 

 female (Plate V, figs. 2, 5, 17, 20, and 23). Notwithstanding the fact that the male 

 and female organs are in general so closely associated, it is more than probable that 

 cross-fertilization occurs quite as frequently, if not more frequently, than close fertili- 

 zation ; since not only are the species as a rule more or less gregarious in habit, but 

 the maturition of the antherozoids invariably precedes that of the trichogyne, and the 

 former continue to be produced long after the latter has been fertilized, in many 

 cases after the perithecium has matured and begun to discharge its spores. This is 

 true of forms having but a single perithecium ; but more strikingly so in those which 

 produce several successive perithecia. In Dimorphomyces, for example, the antheri- 

 dium of the male individual continues to produce antherozoids indefinitely, while the 

 female may produce two or even four sets of perithecia. The same extension of the 

 functional period of the male is also seen in all the genera having compound anthe- 

 ridia. In forms having simple antheridia the same extension of functional activity in 

 the male is often effected by the production of new antheridia! cells or new fertile 

 branches after the fertilization of the trichogyne. 



As has been previously mentioned, the antherozoids are formed, in those genera 

 which produce them exogenously, as lateral branchlets, the whole or portions of which 

 become separated in the form of long slender rods (Plate XXIV, figs. 21, 24 ; Plate 

 XXIII, figs. 21-23), having a definite cell wall, while in the genera producing them en- 

 dogenously the contents of the venter of the antheridial cell are protruded through 



