Botanical Collections, 1 83 



flowers, deprivied totally or partially of pollen, or replaced by a gland, and 

 then the scale belonging to the stamen is much more developed ; so that, 

 according to M. Dunal, the petals are merely stamens of an exterior series, 

 and destitute of anthers ; and, in short, the scales, the petals, the glandular 

 bodies, and the stamens, whether sterile or fertile, are, in his opinion, different 

 states of the same organ. Pursuing this idea, he arrives at the conclusion, 

 that all the parts of a flower, in its perfect state, may be referred to three 

 systems of organs, which are respectively composed of several verticils 

 or series, in the following order: — I. Calycinal system, always sterile; 

 1st verticil, formed of a determinate number of parts, called sometimes 

 exterior sepals ; 2d, composed of parts equal to those of the first verticil, 

 and alternating with them, and often called an exterior calyx ; 3d, usually 

 called the calyx by authors, composed of the same number of parts or sepals, 

 and alternate with those of the second verticil within those of the third series j 

 opposite to them, and often adhering to them, are an equal number of scales, 

 but these, with the sepals, form only one verticil. II. Male reproductive 

 system, or Andrceceum ; this is formed of two ranks, an exterior and inte- 

 rior. Of the former the 1st verticil consists of a number of parts, equal 

 to and alternating with those of the inner verticil of the calycinal system ; 

 this furnishes the petals, in the axils of which are found scales or stamens, 

 but which together form only one series ; sometimes these scales are divided 

 into several, as in the almond : the 2d is of an equal number of parts 

 to the last, and alternate with them. The inner andraeceum has also two 

 verticils ; the 1st has the same number of parts as the others, and alternate 

 with the second verticil of the outer andrteceum ; and the 2d alternates 

 with this. III. Female reproductive system, or Gynceceum, has also two 

 verticils ; the 1st, alternating with the last of the andraeceum, usually 

 constitutes the fruit ; the 2d alternates with this. It appears to be 

 frequently difficult to trace out these nine series ; but notwithstanding^ 

 M. Dunal seems to have proved their existence, and that each constantly 

 alternates with those next it. 



Development of the Ovule In a memoir read before the Institute of 



France, in 1828, M. Mirbel slightly pointed out some discoveries he had 

 made concerning the ovulum of plants ; and, since then, he has published 

 a supplement, detailing his observations. As this may be considered to be 

 a history of his views on the organization and development of ovules, and 

 as the subject is of great importance, we here present an account of it nearly 

 as abridged in the Annales des Sciences Naturelles, vol. xxi. p. 233. 



When the ovula have attained a state of maturity, or, in other words, 

 have become seeds, they may be classed according to one of the three fol- 

 lowing divisions : — orthotropous, anatropous, and campulitropous. The 

 orthotropous seeds are attached to the ovary by their base ; their form is 

 perfectly regular, and their axis is rectilinear. The compulitropous seeds 

 are also fixed to the ovary by their base ; but their form is irregular, and 

 their axis is curved, so that the two ends meet. The anatropous seeds, 

 like the orthotropous, have a rectilineal axis, but they are resupinate on their 

 funiculus, to which they adhere longitudinally, and by means of which they 

 are attached to the ovary at a point near their apex. Before explaining how 

 these forms are produced, it may be first necessary to attend to the different 

 parts of the ovulum. 



The exterior envelope, called by Brown, the testa, and by Mirbel, the 

 primine, receives the funiculus. The point where the vascular fibres of the 

 funiculus traverse the primine, so as to attach it to the second envelope, 

 the tegmen of Brongniart, and secundine of Mirbel, is the chalaza, which 

 Mirbel considers as the organic base of the ovulum. The portion of the 

 funiculus united, in the anatropous seeds, to the primine, is the raphe. 

 The foramen of Brown, micropyle of Turpin, and exostome of Mirbel, 



