242 Dr. L. Kny on the Striicture and 



that a series of divisions takes place in tlie central cell, leading 

 to the formation of the special mother cells. The first septa 

 are usually directed exactly in acconlanee with the longitudinal 

 axis of the antheridium, and placed at right angles to each 

 other in three directions ; afterwards radial walls alternate 

 several times with tangential ones. The cells of the last 

 grade, the number of which is not constant, become rounded 

 oft' from each other. Their very delicate membrane is followed, 

 immediately within, by a hyaline plasma-zone ; the central 

 part of the contents is distinctly granular. 



The opening of the antheridium is here also evidently 

 effected by the turgescence of the two ring cells. After the 

 opercular cell is irregularly ruptured, and the special mother 

 cells are evacuated, these extend themselves inwards, at the 

 same time becoming slightly shortened. By this means are 

 formed radially perpendicular folds, Avhich, when looked at 

 laterally, often present a delusive resemblance to true septa in 

 appearance*. Here also, as in Aneimia Iiirta, we may easily 

 convhiee ourselves, by examination from above, that they do 

 not attain the outer membrane. 



Exceptionally we sometimes observe autheridia with only 

 07ie ring cell. This has then, so far as the mature state en- 

 ables us to judge, exactly the same origin as the vj)j)e7' ring 

 cell in normal autheridia : it is the sister cell of the opercular 

 cell. 



l\ather more frequently autheridia with three ring cells are 

 observed. The middle one, in this ease, is probabl}- formed 

 by a funnel-shaped septum in the same way as the lower one. 

 This was certainly the case in two abnormal autheridia, in 

 which the second ring cell had attached itself laterally and 

 obliquely to the lower one (fig. 16). 



Cihotium Schidei directly approaches -45/j?eniM7?i alatinn, but 

 shows some remarkable peculiarities. The lowest of the two 

 ring cells, Avhich are here present in the great majority of the 

 autheridia, usually rests upon a basal cell which is only deve- 

 loped on one side, and is then lower upon one side than on 

 the other, whilst the upper ring cell is more regidarly deve- 

 loped (fig. 19). The opercular cell does not remain undivided, 

 but is divided into tAvo daughter cells of unequal size l)y a 

 wall, which is perpendicular to the outer wall, but strongly 

 convex towards the middle point of the cell. The larger cell 

 is crescentiform, the smaller one elliptical, pointed at both 



• In two cases I l>elieve I positively ascertained the presence of a sinjjle 

 true lon^tudinal wall in one of the riuj^ cells. I regard them as supple- 

 mentary structures. As to the mode of their production, I can, unfortu- 

 nately, say nothing fm-thcr. 



