ABORTION. 467 



or imperfect development of the indusium, as in what 

 are termed exindusiate varieties.^ 



General remarks on abortion, coincident changes, &c. Refer- 

 ence has akeady been made, while treating of hyper- 

 trophy, suppression, &c., to certain other changes 

 affecting the flower at the same time. Atrophy of one 

 organ or set of organs, for instance, is frequently 

 accompanied by a compensating hypertrophy or by an 

 increased number of other parts. In the feather-hya- 

 cinth, Muscari comosum, var., monstrosum, the absence 

 of flowers is compensated for by the inordinate for- 

 mation of brightly coloured threads which appear to 

 be modified pedicels (see pp. 347, 348) ; so also in the 

 wig plant, Rhus Cotinus. So the atrophy of the sta- 

 mens, in some flowers, is coincident with the hyper- 

 trophy of the pistil. Thus, linger, * Denkschr. d. Kais. 

 Acad, der Wissensch. Math. Nat. Classe,' Mai 25, 1848, 

 p. 103, tab. ix, describes a case wherein the corolla and 

 stamens of Desmodium marylandicum were atrophied, 

 while the calyx and legume, on the other hand, were 

 hyper trophied. 



Fusion of the members of one whorl with one 

 another, or with the components of an adjacent series, 

 often entails atrophy or suppression, either in the 

 united organs themselves, or in adjacent ones. A 

 foliaceous condition of the outer portions, of a flower 

 is very generally attended by atrophy or complete 

 suppression of the inner portions. 



From this point of view the observations of Morren* 

 on the different degrees of atrophy up to complete sup- 

 pression, observable in the flowers of Bellevalia comosaj 

 are of importance. According to this observer, the 

 most highly differentiated parts, such as the stigmas, 

 the ovules, and the anthers, are the first to disappear, 



' See Moore, ' Nature-Printed Fema,' 8vo, for numerous illustrations 

 both of depauperate and exindusiate ferns. Scolopendrium viilgare 

 seems to be one of the ferns most commonly affected in this waj. 

 Moore, loc. cit., vol. ii, pp. 135, 147, 159, 165, &c. 



2 * Bull. Acad. Belg.,'^t. xvii, p. 38, t. 1 ; Lobelia, p. 85. 



