260 Dr. L. Radlkofer on Fecundation in the Vegetable Kingdom, 



Characea. — These plants, hitherto destitute of a fixed home 

 in Systematic Botany, we treat in connexion with their relatives 

 the other Algae, from which they have never been separated but 

 with reluctance or by violence, and among which they will 

 doubtless for the future occupy their right place, namely the 

 uppermost. 



The two kinds of organs of fructification are so conspicuous 

 in these plants, that they were known in the earliest days of 

 observation. The views of the older botanists were in tolerable 

 agreement as to their sexual nature, although direct observations 

 on the act of fecundation itself were and are still wanting. 

 Most recent writers preferred, and justly, to withhold for the time 

 any opinion of the import of the ' globules' (antheridia) . 



Linnseus, from the resemblance in external structure and the 

 order of development, regarded the red ' globules' of Char a as 

 anthers, the spores with their 5-celled envelope (sporange) as the 

 pistil; and ultimately transferred these plants, which he had at 

 first placed among his Cryptogamia*, into the Monoecia Mon- 

 andria f. 



Hedwigt, in whose works we find figures executed with his 

 usual accuracy, so far as the means of observation then accessible 

 permitted, regarded the red granular contents of the oval cells 

 which serve as the peduncle of the triangular external cells of 

 the globules (and upon which appeared to him to depend the 

 red colour of the external cells), as the fecundating matter, — 

 the granular contents of the spore, exclusive of the starch- 

 granules, as the proper seeds. 



Vaucher§, Kaulfuss ||, Bischofi"^, C.H.Schultz**,and K.Miil- 

 lerft each observed the entire development of plants resembling 

 the mother-plant from the spores. In this operation the spore 

 {nucule) ordinarily first loses its cellular covering [sporangium) y 

 the outer coat of the spore opens at the upper end of the spore, 

 and the inner cell expands into the first cell of the young plant. 



FritscheJJ furnished an exact description and representation 

 of the globules (antheridia) and the spiral filaments contained in 



* Genera Plant. Ed. 6. Holm. 1764, p. 667- 



t Systema Naturae. Ed. 12. Holm. 1/67, ii. p. 613. 



X Theor. Generat. et Fructif. Plant. Crypt. &c. Petrop. 1784, p. 125. 

 pi. 22, 33. 



§ Mem. sur les Charaignes. Memoires de la Soc. de Phys. et d'Hist. nat. 

 de Geneve, i. pt. 1. p. 168 (1821). 



II Erfahrung. uber das Keimen der Charen. Leipsic, 1825. 



1[ G. W. Bisehoif, Krypt. Gewachse. Nuremb. 1828, p. 9. 



** Natur der lebenden Pflanze, B. ii. 



ft K. Miiller, Zur Entwickl. der Charen. Botan. Zeit. 1845. (Transl. 

 in Ann. Nat. Hist. xvii. p. 254.) 



