88 HOFMEISTER, ON THE HIGHER CRYPTOGAMIA. 



Gottsche is of opinion that the antheridia of the liver- 

 worts in general have a wall consisting of a double layer of 

 cells — an inner layer, the cells of which become detached 

 when ripe and contain colouring matter, and an outer layer 

 of hyaline, tubular cells, of small height, with transparent 

 fluid contents. Gottsche's opinion is founded mainly upon 

 investigations of Haplomitrium Hookeri. He attributes a 

 similar structure to the antheridia of Fossombronia.* He 

 is decidedly in error in both cases ; the covering layer 

 is certainly a single layer of cells, which, when the 

 organ is fully ripe, give way at the apex, and separate 

 from one another. This cannot be a matter of doubt 

 to any one who witnesses the spontaneous opening of 

 an antheridium under the microscope. But the structure 

 of the covering layers, even in antheridia, which are still 

 closed, can be fully made out with a good microscope. 

 Gottsche's view may have originated in the circumstance 

 that in Fossombronia, as well as in Anthoceros, the coloured 

 bodies often lie close to the inner side of the wall of the 

 cells of the covering layer, so that the somewhat swollen 

 protuberance of the free outer wall appears to be filled 

 merely with a clear, watery fluid. 



With regard to the outer of the two cellular layers of the 

 covering of the antheridia of Haplomitrium, a preparation 

 of which has been figured by Gottsche (1. c, t. xvi, f. 8), 

 I find that the antheridia of this plant are similar to 

 those of Sphaginum ; that a thin glassy cuticle encloses 

 the simple covering layer of the antheridia. In Haplo- 

 mitrium the boundaries of the cells appear upon this 

 cuticle in the form of prominent ridges, but this is not 

 the case in Ephagnum icymbifoliutii). The cells of this 

 covering layer isolate themselves at the time of the ripen- 

 ing of the antheridia of Sphagnum, precisely after the 

 manner of the cells of Haplomitrium ; a median lamella of 

 the wall of the cells swells up into a gelatinous substance. 

 By this means the vermiform cells become detached from 

 one another, and separated from the cuticle. 



* /. c, vol. xx, p. 291. 



