24 Mr. A. H. Hassall on the Anatomy and Physiology 



is cruciform and adherent to the interior wall of the cell. It, 

 Mr. Bowerbank remarks, is probably the vegetable structure 

 which secretes the raphides. The other body is small, elongated, 

 somewhat curved, and attached to or lying upon the plant. This, 

 Mr. Bowerbank observes, is certainly a " string of minute cyto- 

 blasts ; and similar bodies, but more curved, are observed in the 

 soft parts of the young lips of shells, both land and freshwater .^^ 

 More than one of each of these organs may be found in each cell. 

 For representions of these see fig. 1. 



The Rev. M.J. Berkeley has kindly favoured me with an abs- 

 tract of a paper by Hugo Mohl on the genus Anthoceros, pub- 

 lished in 1839 and inserted in ' Linnsea,^ vol. xiii. p. 273, in the 

 cells of which an organ occurs bearing a considerable external 

 resemblance to the radiated structure met with in the cells of 

 Zygnema. 



The following is a brief outline of the mode of formation of 

 this structure in the genus Anthoceros. When an immature cell 

 of one of the species of this genus is examined, a portion of its 

 interior is seen to be occupied by a layer of green granules, 

 through which may be seen a cytoblast, the other portion of the 

 cell being colourless. Treated with iodine, the layer formed by 

 green granules, as also the colourless part of the cell, becomes yel- 

 low, showing that the whole is really lined with a sort of quasi 

 membrane. Gradually the green layer becomes concentrated 

 into two masses, which commence to advance more and more 

 towards the middle of the cells, and the edges of these masses 

 spreading in various degrees over the inner wall of the cell, leave 

 intervals of various sizes, which give to them a cellular appear- 

 ance. " The nucleus or cytoblast," Mohl observes, '' has no part 

 in this formation. Frequently it is so concealed beneath the green 

 granular mass that it cannot be seen without some trouble ; some- 

 times it lies near to or between both divisions of the green mass 

 and then more easily comes into sight, but at the same time it is 

 observable that it remains unaltered and is foreign to the whole 

 of the slimy structure described above. The latter seems only so 

 far to have a relation to it, that its point of concentration is always 

 at the place where the nucleus lies, and indeed between it and the 

 walls of the mother cell." 



Subsequently, the two masses become divided into four, and the 

 reticulated appearance produced by the spreading of the masses 

 subsides into radii, which are similar in aspect to those emana- 

 ting from the cytoblast in the Zygnemata, each arising separately 

 from the masses and terminating on the inner surface of the cell. 

 Finally, each radiated mass becomes a perfect spore or cell, sepa- 

 rated from each other by distinct cellular walls, in which changes 

 similar to those just described take place for the production of 



