• GENERATIVE ORGANS IN FLORIDE^. 331 



the projection and narrowing of one end into a kind of footstalk, 

 by which the spore attaches itself, its form passing from the 

 globular to the pear-shaped ; a partition is speedily observable 

 in its interior, its single cell being subdivided into two ; and by 

 a continuation of a like process of duplication, first a filament, 

 and then a frondose expansion, is produced, which gradually 

 evolves itself into the likeness of the parent plant. The whole 

 of this process may be watched without difficulty, by obtaining 

 specimens of F. vesiculosus at the period at which the fructifica- 

 tion is shown to be mature, by the recent discharge of the con- 

 tents of the conceptacles in little gelatinous masses on their 

 orifices ; for if some of the spores, which have been set free 

 from the olive-green (female) receptacles, be placed in a drop of 

 sea-water in a very shallow cell, and a small quantity of the mass 

 of antherozoids set free from the orange-yellow (male) recepta- 

 cles, be mingled with the fluid, they will speedily be observed, 

 with the aid of a magnifying power of 200 or 250 diameters, to 

 go ijirough the actions just described; and the subsequent pro- 

 cesses of germination may be watched by means of the " grow- 

 ing-slide."' The winter months, from December to March, are 

 the most favorable for the observation of these phenomena; but 

 where the Fuci abound, some individuals will usually be found 

 in fructification at almost any period of the year. Even in the 

 Fuaacece, according to recent observations, a multiplication by 

 zoospores, like that of the Ulvacese (§ 195), still takes place ; 

 these bodies being produced within certain of the cells that 

 form the superficial layer of the frond, and swimming about 

 freely for a time after their emission, until they fix themselves 

 and begin to grow. That they are to be considered gemmce, 

 and not as generative products, appears certain from the fact 

 that they will vegetate without the assistance of any other bodies ; 

 whereas the antherozoids of themselves never come to anything, 

 and the octospores undergo no further changes, but decay away 

 (as M. Thuret has experimentally ascertained), if not fecundated 

 hj the antherozoids. 



206. Among the Rhodospermeoe, or red Sea-weeds, also, we find 

 various simple but most beautiful forms, which connect this 

 group with the more elevated Protophytes, especially with the 

 family Ohcetophoraceoe ; such delicate feathery or leaf-like fronds 

 belong, for the most part to the family Oeramiacece, some members 

 of which are found upon every part of our coasts, attached either 

 to rocks or stones, or to larger Algse, and often themselves afford- 

 ing an attachment to Zoophytes and Bryozoa. They chiefly live 

 in deeper water than the other sea-weeds ; and their richest tints 

 are only exhibited, when they grow under the shade of project- 

 ing rocks or of larger dark-colored Algse. Hence in growing 



' If a cell be not employed, the drop should not be covered, unless some precaution 

 be taken to keep the pressure of tlie thin glass from the minute bodies beneath, whose 

 movements it vifill otherwise impede. 



