"Mv. H. J. Carter on Fecundation in CEdogonium. 33 



one3 which t;ike phicc in the male filament, the annuhir cells of 

 which apj)ear to be oi)eiied by genieulatiou or dehiscence, which 

 separating them from each other on one side, thus ruptures the 

 partition portion of the cell-wall, &c., and permits the sperma- 

 tozoids to escape into the water (fig. 8). When here, they at 

 first remain stationary for a few seconds, to recover themselves 

 from the shock of delirery, and then bound away in search of 

 the resting-s])ores. 



Having arrived at the micropyle, they now beat about it with 

 the ciliated extremity for some time, occasionally causing the 

 cell- wall to yield perceptibly before their pressure, until, by 

 chance, they hit the right point, when they squeeze themselves 

 through the aperture, and thus pass into the vacuity above the 

 spore (tig. 5). Here, again, they repeat the beating movement, 

 and evince various other motions indicative of their desire to 

 enter or become incorporated with the rcsting-spore, which, if 

 ineffectual, ends in their becoming stationarily fixed to its cir- 

 cumference or some part of the spore-cell wall (fig. 6). 



In this way I have seen scores of instances in which there 

 have been one to three spermatozoids in the spore- cell at the 

 same time, — all in active movement, or one or two only moving 

 or fixed, as the case might be; or one or more, more or less 

 active ; while in many instances they appeared to be half-ineor- 

 jjorated with the spore (fig. 6), and in one case I thought that 

 1 could see the end of a spermatozoid in the transparent portion 

 of the spore, after it had passed into it. But in this species I 

 have never seen the act of incorporation itself take place, although 

 I have kept rcsting-spores with one or more spermatozoids in. 

 active movement on them, for several hours together, under 

 observation. 



Hence I am inclined to infer that, for the completion of this 

 process, it is necessary that the pellicles of both resting-spore 

 and spermatozoid should be in a semi-fluid state; while that, 

 when one or both become hardened, which appears to be a na- 

 tural consequence, not under the control of either resting-spore 

 or spermatozoid, the process must be cheeked. Again, as this 

 is precisely the case with Spirogyra, which appears in all stages 

 of arrest under sporing, so the separate globular form of the 

 spermatozoid within the spore-cell, appearing in every degree 

 from this up to its almost entire incorporation with the resting- 

 spore in (Edoffonium, seems to indicate that these are also arrests 

 of incorporation from a similar cause, viz. the progressive 

 hardening of the pellicle. 



Let us now^ turn our attention to the sporing of the next spe- 

 cies, viz. (E. diandronites, which I obtained from the same tank 

 as the foregoing one, separate and also in company with it. 

 Ann. i^ Mag. N. Hist. Ser.3. Vol.'x. ' 3 



