106 MR. HENFREY ON THE DEVELOPMENT OF THE SPORES 



between the latter and the columella ; while in the Hepaticce where the inner membrane 

 is wanting, they run in free among the parent-cells of the spores." 



Von Mohl* gives no account of the development of elaters ; with regard to certain of 

 his views on the development of the spores, I shall allude to the papers just cited, 

 further on. 



Gottschet does not describe the development of the elaters, nor indeed the earlier 

 conditions of the spores. 



I now proceed to the results of my own researches on this subject. 



The little green cellular body which is found within the pistillidium increases in size, 

 and in the course of its growth its cells are differently modified ; the external layers, over 

 the whole surface, adhere together into a membrane, which becomes the spiral-celled 

 membrane of the capsule ; the cells contained within this layer produce the spores and 

 elaters. I have not been able to determine satisfactorily the earliest conditions of the 

 enclosed cells. In the youngest specimens I found it impossible to ascertain the true 

 nature of the structure, on account of its delicacy, but I believe that Bischoff is certainly 

 wrong in supposing the young capsule to be filled with a mucilaginous fluid (brei). 

 Mr. Griffith and M. Mirbel state, that there exists a continuous tissue in Targionia ; and 

 Mr. Pitt J states that the apparently gelatinous contents of the capsule of Sphcerocarpus 

 terrestris exhibited a cellular appearance, when dried up, on the object-glass. From these 

 facts and from analogy, I am inclined to believe that the young capsule is at first 

 formed of a continuous cellular structure, and that the cells of this tissue become parent- 

 cells, producing new cells within them, which they set free by becoming dissolved; 

 exactly as occurs in the production of the parent-cells of the pollen-grains, in the con- 

 tinuous cellular tissue of anthers. 



However this may be, it is certain that cells do become free in the cavity, producing the 

 elaters and spores, and the condition and form in which they present themselves is very 

 remarkable. M. Mirbel states that he found minute elongated cells, the young elaters, 

 mingled with small squarish cells, the spores, which afterwards acquired a globular form. 

 It is evident from this that he missed the earlier stages of the metamorphoses. I found 

 the young capsules to contain elongated cells alone, and these of two sizes. The whole 

 cavity of the capsule was filled up by elongated cells arranged side by side, and apparently 

 radiating from the centre; a portion of these elongated cells were narrow, and were 

 interposed between much longer and broader ones of the same form, in such a manner 

 that scarcely any interspaces existed. The narrow cells are the young elaters, while the 

 broader ones are the parent-cells of the spores. The subsequent development I have 

 followed out clearly. The young elaters are elongated, slender tubes, attenuated toward 

 each extremity ; they are at first filled merely with an almost colourless, coagulable pro- 

 toplasm. After a short time starch-granules make their appearance in them, the true 



* Ueber die Entwiekelung und den Bau der Sporen der Crypt-Gewachse, Flora 1833; Vermischte Schrift. 67. 

 Ueber die Entwiek. der Sporen von Anthoceros lavis, Linnsea 1839 ; Verm. Schrift. 84. 



t Ueber Haplomitrium Hookeri, Nova Acta, vol. xx. Ueber die Fructification der Jungermannise Geocalycese, 

 Nova Acta, vol. xxi. 



% London Journal of Botany, vol. vi. 



