Dr. A. Braun on the Vegetable Indmdual. 371 



Cams* called attention, and IJeichert, his predecessor, as 

 well. 



The difficulties which the qualitative differences of shoots of 

 one and the same species seem to present to our conception of 

 shoots as individuals, will be entirely obviated if we can demon- 

 strate that a partial outfit and equipment of individuals, perfectly- 

 analogous to those found among plants, are likewise found in 

 the animal kingdom, where in most cases there is less doubt as 

 to what is an individual, — if we can show that in both kingdoms, 

 and in a similar manner, a polymor|)hism of individuals occurs 

 which depends upon a division of the steps of development and 

 of the vital problem of the species among individual members, 

 whether of the same generation (divisions of generation), or of 

 different generations cyclically succeeding each other (alternation 

 of generation). 



Let us first compare the phsenomena of alternation of gene- 

 ration (or, as it should be called, cyclical succession of (jene- 

 rations) in both kingdoms f. As is the case in the alternation 



* Zur niihereu Keuutaiss. d. Generatioasw. (1849); and, Einige Woi-te 

 lib. Metatn. u. Generationsw. (vou Siebold u. KoUiker, Zeitschr. f. wiss. 

 Zool. iii. 1851, p. 359). 



t These remarks on alternation of generation in plants, do not depend, 

 as one might perhaps be disposed to think, upon a zoological doctrine 

 fancifully apjjlied to plants. But I recognized the phsenomenon as the 

 same, and I treated of it in my papers, if not under the same name, still in 

 the same meaning, before my attention was called to the occurrence of this 

 pha;nomenon in the animal kingdom by Steenstiup's work. As soon as 

 the doctrine of the shoot as the vegetable individual was assumed in all its 

 consequences, a determinate succession of generations emitted one from 

 the other necessarily appeared to be the ground of the flower's first making 

 its ajjpearance in many plants in a determinate degree of ramification, and 

 of the occurrence of a determinate succession of steps in the series of axes 

 up to this goal, caused by a peculiar ])art;ti()n of the leaf-formations. 

 Hereby the essential shoot-succession, which is the one which rejjresents 

 alternation of generation, was accurately distinguished from the unessential 

 one. Twenty years ago, or more, C. Schimper distinguished between 

 essential and unessential shoots, denominating the first (in a wider sense of 

 the word) "• Ableger" [off-sets], the latter "Ausleger" [out-sets]. In the 

 ' Vcrsammlung d. Naturforscher * in Mayence in the autumn of 18-12, 1 made 

 a communication on this subject, and at the same time in particular I 

 called attention to the frequent importance of the characteristics involved 

 in these relations when applied to improving the differentiation and group- 

 ing of species. Of this comnmnication a re])ort a])peared in the ' Flora ' for 

 1842, ]).9f)2, though, indeed, somewhat distorted by inaccuracies. Wydler 

 treated the same subject in the ' Bot. Zeit.' 1844, St. 37, under the heading 

 " Achsenzahl der Gewachse," and gives a compendium of examples, in 

 which, however, much ajipears which needs qualification. As Wydler in- 

 forms us, Aug. de St. Ililaire is said to have turned his attention to ascer- 

 taining the number of essential axes in ])lants ; however, I find nothing in 

 the place referred to in the ' Lecons de Botanique ' but the distinction be- 

 tween determinate and indeterminate growth, which has been known since 



2-1* 



