86 HOEMEISTER, ON 



top at the time of impregnation, and then traversed in the 

 longitudinal axis by a canal ; as organs out of which at a later 

 period the calyptra, crowned with the neck of the archego- 

 nium, is developed. Our knowledge of the structure of 

 these organs had made no progress since the time of 

 Hedwig until my own observations were published.* 



Prior to my own observations, the very young condition of 

 the fruit had only been seen by Gottsche twice in Calypo- 

 geia TricJiomanes, in the form of a two- or three-celled body at 

 the base of a wide cavity of the calyptra, and which Gottsche 

 considered to have sprung from the base of such cavity. f 

 At a somewhat later stage of development of the young 

 fruit, Gottsche saw indications of the formation of the same 

 out of four rows of cells trending downward to the one 

 basal cell, but he could not make out the matter clearly. 

 Schmidel had abeady observed the well-defined limits 

 between the lower end of the fruit-stalk and the tissue of 

 the stem into which that end is sunk ; J as also had Hedwig, § 

 who had observed the many toothed sheath around the 

 base of the fruit-stalk in Fellia epiphylla. 



With respect to the development of the spores of the Jun- 

 germannise, H. von Mohl established the fact that they are 

 formed in fours, in round mother-cells, and that the elaters, 

 as long as the spores are lying unformed in the mother-cell, 

 have the shape of spindle-like, delicate-walled cells, standing 

 in no organic connection with the spore-mother-cell. Von 

 Mohl also observed that the young oval spores of Pettia 

 epiphytta, whilst still hanging together in fours, are only 

 in contact with one another by a small portion of their upper 

 surface. || 



The membrane of the perfect elater had been noticed by 

 Von Schmidel in Aneura multifida^ Nevertheless, the 

 notion of " naked elaters " was prevalent until a recent 



• Compare C. G. Nees v. Esenbeck, 1. c, p. 60; Gottsche, 1. c, p. 315. 

 f ' Nova Acta,' Ac. C. L., xxi, pars ii, 445, 447. 

 % ' Icones plantarum,' iii, Erlangen, 1797, Tf. 57, f. 14, J. exsecta. 

 \ 'Theoria generations, ' t. xvii, f. 10; /. nemorosa, t. xxiv, f. 4; xxv, f. 2, 

 Pellia epiphylla. 



|| ' Mora/ 1833. ' Vermisclite Sckriften,' p. 63. 

 f ' Icou. plant,,' t. lv, f. 13. 



