THE ANNALS 



AND 



MAGAZINE OF iNATURAL HISTORY. 



[SECOND SERIES.] 

 No. 71. NOVEMBER 1853. 



XXVIII.— On the " Nucleus" of the Characeae. 

 By Al. Braun*. 



[From his Memoirs on the Circulation in the Characeae.] 



In the cells immediately sening for the reproduction of the 

 Characeae, the germ-cell or spore and the mother-cells of the 

 spermatozoids, there is no circulation of the sap, but a cir- 

 culation is met with in various cells of the enveloping organs, 

 through the medium and under the protection of which the 

 essential reproductive cells are produced. I cannot avoid dis- 

 cussing a few general points connected with these most pecu- 

 liarly formed organs of the Characeae, the import of which has 

 been explained in the most varied ways. The organs in question 

 arc of two kinds. The one, the seat of formation of the sper- 

 raatozoids, usually named, in avoidance of any functional signi- 

 fication, simply the globule, formerly regarded as an anther, and 

 even as a pollen-grain f, or erroneously asserted to be a bud ca- 

 pable of germination :J:, is now generally termed the antheridium. 

 Aberrant as its structure is from all other known antheridia, it 

 appears to me, from its centripetal development, to possess a 

 certain agreement with the antheridia of the Mosses and Liver- 

 worts, so that I cannot, with Hofmeister (Flora, 1851, No. 1), 

 term it a convolute of many antheridia or a ' head ' of an- 

 theridia. In the antheridium are formed the active seminal 

 filaments {spermatozoa, antherozoidia), which were first seen by 



* Monatsber. K. Preuss. Acad. Jan. 1853. Translated by Arthur Hen- 

 frcy, F.R.S. &c. 



t Meyen, Linna;a, 182/, p. 63. 



:J: Wallroth, Ann. Bot. 1815, p. 170. Reichenbach (Flor. Germ. exc. 

 p. 147), on the contrarj-, regards the female organ as a bud, and the globule 

 as an androgynous flower with eight pistils and numerous staminodia. 

 • Ann. ^- Alag. N. Hist. Ser. 2. Vol. xii. 21 



