600 PROCEEDINGS OF THE ACADEMY OF [NoV. 



threads remained green over the winter, but, being few, they were 

 not noticeable to the naked eye. 



The quantity of starch in the bleached cells varied considerably. 

 The extreme condition, on the one hand, where the cells were 

 quite full of starch, as in fig. 1, is markedly different from the 

 rather starved condition of figs. 5 and 6. In the latter cases the 

 cells are doubtless still alive, but they contain comparatively little 

 starch and great vacuoles. The vacuoles are well brought out on 

 treating the cells with iodine (fig. 6). 



The plant, as a whole, is certainly in a living and, I believe, 

 actively growing condition, and it looks as though it were i*egaining 

 its normal activity. Extremes and transitions, as regard the 

 quantity of chlorophyll present, can easily be observed. Com- 

 parisons of figs. 1, 7, 9 and 2 will illustrate this point. Fig. 1 

 shows the perfectly bleached cell, figs. 7 and 9 show cells contain- 

 ing a little chlorophyll, while fig. 4 repressats the deep green 

 cell, which consists of one large mass of connected chromatophores. 

 Furthermore, such cases as that of fig. 2, which I mentioned above, 

 were to be found where the whole cell was colored, but the green 

 tinge a very faint one. 



The filaments come singly or in groups from basal cells (figs. 8, 

 9. and 10). In many cases these basal cells are green, while the 

 remainder of the filament may be either green or bleached. Fig. 

 9 represents a case where the basal cell is white. 



The normal state of affairs is the following: The vegetative 

 condition finally results in the formation of oogonia. These are 

 the only portions of the plant which survive the winter, and are 

 protected from cold and moisture by their thick cell walls.* In 

 this instance the oogonia Avere not formed, and the food which the 

 plant had stored up for this normal function remained in the form 

 of starch. Naturally it will be of interest to find out if the plant 

 will again resume its assimilating activity. It would also be of 

 interest to determine if the plant behave similarly out of doors, 

 which it might well do under the conditions of a mild winter or in 

 protected places. At all events, the fact that the plant continues 

 to live in its present ghostlike condition seems an interesting reve- 

 lation, so far as the physiology of algie is concerned. 



In Leunis' Synopsis der Botanik^ I found the following state- 



^ Luerssen, Orundzuge der Botanik, p. 191. 



' Leiinis, Synopsis der Botanik, Bd. Ill, pp. 163, 164. 



