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TRANSLATIONS. 



Algarum Unicellularium Genera nova et minus cognita, 

 prcemissis Observationibus de Alois Unicellularibus 

 in genere. 



New and less known Genera of Unicellular ALGiE, preceded 

 by Observations respecting Unicellular Alg^ in general. 

 By Alex. Braun. (Lipsise, 1855 ; with six Plates.) 



Continued from No. XVIII^ p. 96. 



The organs of fructification, and in particular the cells, by 

 which the Algce and cryptogamous plants in general are 

 propagated, have received the most various names, for the 

 most part insufficiently defined and applied in different 

 senses.^ Propagative cells undoubtedly occur widely differ- 

 ing among themselves, and frequently differing, and this is a 

 point of the greatest importance, in the same plant. f For 

 some differ but little, others as widely as possible from the 

 vegetative cells ; some are endogenous in their origin (in a 

 simple parent-cell, or in two conjugated ceUs), some acro- 

 genousjj they may be enclosed in a membrane either soft 

 or rigid, simple or multiple ; they may be inert or active 

 (furnished with motile cilia) ; some are subservient to fe- 

 cundation either in a direct § or indirect || manner, some to 

 germination, others altogether sterile.^ Among those which 



* The following terms have chiefly been employed : siwra, sporidium, 

 sporidiolum, spermatium, speirema, spharospora, zoospora, gonidium, gemmi- 

 dium, conidiuni, gongi/bis, spermatozoidium, antherozoidium, &c. 



f Fructification of the double kind is extremely common ; of the triple 

 kind instances are afforded amongst the Algce, in most of the Floridea:, in 

 (Edogonmm, Vaucherla, Saprolegnia, and Chlamidococcus ; among the Lichens, 

 in Scuhda (Tulasne, 'Ann. d. Sc. Nat.,' 17, p. 118, t. 14); among the 

 Fungi, in Cenangium Frangulce (Tulasne, 1. c., 20, p. 136, t. 16), Bulgaria 

 (ib., p. 129, 1. 15), Bacrymyces (ib., 19, p. 211, 1. 13), Erysiphe, Stemphylium 

 (De Bary, 'Verb, des pr. Gartenbauer,' 1853, p. 178, t. 2), Feronostoma 

 (from the very recent observations of Caspery), &c. 



% Conidia, stylospores, basidiospores, and spermatia of the Fungi and 

 Lichens. 



§ Spermatozoidia of the Filicoidecs, Muscoidece, Fucoidece, Floridea ; sper- 

 matia of Lichens and Fungi. 



II Microspores of the LycopodiacecB and Rhizocarpece. 



% Most microgonidia (Chlamidococcus, Pediastrum, Stephanospheera, Hy- 

 drodictyon^ Cutleria), i\xG psemlo-gonidia (spermatosphceria, Itzigs.) of Spiro- 

 gyra, &c. 



