258 ON THE PLACE OF CHAEACE^ IN THE NATURAL SYSTEM. 



ON THE PLACE OF CHARACE.E IN 

 THE NATUEAL SYSTEM. 



By Prof. T. Caruel. 



Mr. Bennett has discussed this subject in an interesting paper 

 which appeared m the ' Journal of Botany' for July (p. 202), con- 

 densing in a few jDages most of what has been written on the 

 structure and affinities of Cliaracece. He has incidentally mentioned 

 the place I have given them, as forming a separate division (or 

 primary groujD) beetween Phanerogams and Prothallogams ; but 

 as he has not recorded my reasons for so doing, perhaps some 

 explanation on vaj part will not come amiss. 



In my recent book on Morphology ''' I have tried to bring mto 

 full light the fact that all vegetable organisms (except the veiy 

 lowest) are reiu-eseuted in every species by three different forms, in 

 alternating generations, viz., a neutral form, producing, either 

 directly or indirectly, two sexual forms, which by their action on 

 each other reproduce the neutral form. Now these present different 

 and even opposite characters, according to the various series of 

 plants ; and of such I have availed myself to define better those 

 large primary divisions of the vegetable kingdom that, under dif- 

 ferent names, are now admitted by all botanists. In Bryogams 

 (Mosses), and those Gymnogams that are trimorphous (such as 

 Oedogoniaceoi), the female form is indefinite in its evolution, and 

 organized so as to produce in succession a long series of arche- 

 gonia and thence embryos (or of oogonia), and of antheridia, 

 which last produce the phytozoa or male form ; while the neutral 

 form is, on the contrary, definite in its evolution, in Mosses begin- 

 ning as an embryo, and terminating shortly by the formation of 

 the urn at one end. In the remainder of the vegetable world the 

 process is reversed : it is the neutral form that is indefinite, while 

 the female forms (gemmule in Phanerogams, prothallus in Ferns 

 and their allies) are definite, only once producing the embryo of 

 the neutral form. And such is the case with Cliaracea:, which can 

 therefore by no means be brought together either with Mosses or 

 with Ah I a. 



Much stress has been laid on the supposed similarity between 

 Characea and Mosses, from the cu'cumstance that these last, when 

 they are cormophytes, begin by a filamentous thallus, on which 

 subsequently buds are formed ; and CJiaraccic have been deemed to 

 act likewise. But notwithstanding the high authority of those 

 who support this view of the case, I own I cannot side with them. 

 A careful examination of the process of germination in Characecr, 

 as exposed by Pringsheim and De Bary, shows indeed the lateral 

 formation of buds on a previous sim^Dle shoot ; but as this con- 

 temporaneously gives out leaves on the other side, it can be 

 considered in no other light than as a stem, and nowise as 



* Shortly noticed at p. 170. — [Eu.] 



