128 DUBLIN UNIVERSITY 



each by its own special coat, — not, as in Desmidiaceae, according to 

 Hofmeister, the expansion of the " younger inner layer of membrane not 

 firmly adherent to the older portions." But, again, both our Dublin plant 

 and Hofmeister' s appear to have some affinity to Glaeocapsa. In them, 

 however, there is enclosed, in the loose outer cell-membrane, only one 

 green cell, — not as in Glacocapsa, 2, 4, 8, &c. But there does appear, 

 perhaps, a greater similarity in the separate persistence for some time of 

 the outer cell- wall in each. In Glaeocapsa the outer concentric layers, 

 formed by their solution into a confluent gelatinous mass, usually remain 

 in some numbers — in M. Hofmeister' s plant he states to the number of 

 six sometimes — the chief difference in this respect apparently being, that 

 they do not, as in Glaeocapsa, become gelatinous, but are eventually cast 

 off as loose wrinkled membranes. The green cells sometimes escape from 

 Glaeocapsa, too, by a fracture at the side, leaving behind the empty con- 

 centric layers. 



It is greatly to be hoped that upon a study of his plant M. Hofmeister 

 may decide upon " a local habitation and a name" for it (and along with 

 which, I apprehend, our plant must follow), which, simple in form as it 

 may be, appears a sufficiently puzzling problem. I have, nevertheless, 

 thought it possible that this imperfect notice of the occurrence with us 

 of an organism, at all events closely allied to, if not identical with, that 

 alluded to by that distinguished author in his most valuable paper, 

 might possibly, to our local observers at least, possess some interest. 

 Others may have met with the same plant, who, while abstaining from 

 making them public, may have carried out further and far more conclu- 

 sive observations ; and if, by drawing attention to this plant, I should 

 be the unworthy means of eliciting their information, I shall have done 

 some good, and my object in coming forward will have been accom- 

 plished. 



DESCRIPTION OF PLATE XI. 



Fig. 1. Represents a single detached joint of Leptocystinema Kinahani, 

 ife of an inch in length, magnified 330 diameters, showing the 

 broad view of the compressed band of endochrome, with its 

 longitudinal median series of corpuscles, central interruption, 

 and terminal clear spaces and granules. 



