314 MORPHOLOGY. 



me, and have in part confirmed the correctness of my views. The first 

 was Geleznoff in Tradescantia virginica (Bull, de la Soc. Imp. des Nat. 

 de Moscau, torn. xvi. 1843). He was still doubtful whether the stamens 

 did not arise earlier than the corolla. Duchartre spoke more decidedly 

 on this point, with regard to the Malvacea (Compte rendu, 1844, seance 

 18 Mars), and the PrimulacecB (ibid, seance, 18 Juin). On the other hand, 

 Barneoud confirmed my observations completely, through the investiga- 

 tion of the PlantaginacecB and Plumb aginacece (Compte rendu, 1844, 

 30 Juli). Strangely, he says *, that the course of development of the 

 flower follows, against my theory (!), from without inwards, which on 

 account of the figures given by Vogel and myself, cannot be excused, 

 even on the plea of ignorance of the German language. 



It has often been attempted to develope the morphological laws of the 

 structure of flowers from monstrous formations. I believe that this 

 attempt is altogether faulty, even presupposes a total ignorance of the 

 value and import of the progressive development. If up to this point 

 one must reject every application of the analogy of animals to plants, it 

 were yet very desirable that most botanists should go through a thorough 

 course of zoological physiology, so that they might, at least in some de- 

 gree, learn method in the treatment of organic bodies. Whoever has 

 traced the course of development of even a couple of only rather difficult 

 flowers, will have certainly become convinced that every conclusion from 

 the developed flower as to its regular rudiments, and the import of its 

 parts, must inevitably be faulty, and that monstrosities, double and pro- 

 liferous flowers, such as are transformed into leaves, &c., require eluci- 

 dation by the history of development just as much as the normally 

 formed flower itself. Even Mohl might have spared himself his so 

 acutely carried out examination of Poa vivipara, and the explanation of 

 the flower of Grasses deduced from it (Botan. Zeit. b. iii. p. 33), if he 

 had only convinced himself, in the flower of a single Grass or of a single 

 Carex, how by a subsequent one-sided development, the most perfect 

 symmetry becomes wholly hidden. I have thought myself obliged, 

 especially for a better understanding of the importance of the course of 

 development, to care for it in publishing several of the more difficult or 

 more instructive instances in the accompanying plates ; namely, in Plate 

 III. the course of development of the leaf of Pisum sativum, of the 

 flower of Agrostis alba, of Carex Lagopodioides and Ccmna exigua ; 

 and in Plates IV. and V. a more complete illustration of the development 

 of the flower of Passiflora princeps. 



145. In Phanerogamic flowers the following parts are distin- 

 guished, proceeding from without in wards: 1. The floral envelopes, as 

 the external calyx (epicalyx), of which the parts are leaves (phi/lla); 

 the calyx, the parts of which are sepals ; the corolla, the separate 

 portions of which are petals; or, instead of these three, the perianth 

 (periantliiurn), whose separate parts are leaves (phylla): 2. The sta- 

 mens (stami7ia), around and within which some stunted acces- 

 sory foliar organs appear under very various names : and, lastly, 

 3. In the centre of the flower, the pistil (pistillum), the separate 

 foliar organs of which are carpels (carpella}. In the stamens the 

 lower thread-like portion, which is termed the filament (filamen- 



* At least in the extract in the Botanische Zeitung, 1845, p. 115. 



