lx INTRODUCTION. 



The Stamens are undoubtedly the apparatus by means of which vivid- 

 cation is communicated to the ovula or eggs. They either arise immediately 

 from below the ovarium, having no adhesion to the calyx, when they are said 

 to be hypogynous, or they contract an adhesion of greater or smaller extent 

 with either the calyx or corolla, when they become perigynous, or, finally, 

 they appear to proceed from the apex of an inferior ovarium, in which case 

 they are named epigynous ; but it is usually now understood that all sta- 

 mens take their origin from below the ovarium ; and if this opinion be 

 well founded, there will be no material difference between those which are 

 perigynous and those which are epigynous ; and these two modifications 

 are accordingly confounded together by most modern botanists. M. Ad. 

 Brogniart, however, conceives epigynous stamens to be essentially distinct 

 from perigynous, founding his opinion upon the genus Raspailia, which 

 has a superior ovarium, from the top of which arise the stamens ; but it is 

 possible perhaps to explain this apparent anomaly. To the difference be- 

 tween perigynous and hypogynous stamens the French school attaches 

 the greatest value, not being willing to admit any genus with hypogynous 

 stamens into an order with perigynous ones, and vice versa ; and there is 

 somewhere an observation, that of such primary importance is this distinc- 

 tion, that while poisonous orders are to be known by their stamens being 

 hypogynous, all in which they are perigynous are wholesome. Setting 

 aside, however, this hypothesis, which has not the general application that 

 has been ascribed to it, there is no doubt that insertion of stamens does 

 very often go along with essential differences of other kinds ; for example, 

 it distinguishes with precision Rosacea? from Ranunculacece, Violaceae from 

 Passifloreae, Reaumurieae from Nitrariaceae, Aurantiaceae from Bursera- 

 cese. But, on the other hand, there is not only frequently, as may be well 

 supposed, so slight a degree of adhesion between the stamens and calyx 

 as to render it difficult to say whether the former are perigynous or hypo- 

 gynous, as in Galacineae, Tamariscineae, an} many others ; but there are 

 orders which do really exhibit instances of both modes. Thus Eschscholtzia 

 has decidedly perigynous stamens, and yet it is undoubtedly a genus of 

 Papaveraceae, the character of which is to have them hypogynous ; and 

 all kinds of gradations, from the one form to the other, are observable in 

 Saxifrageae. The stamens of Macrostylis, among the hypogynous order 

 Diosmeae, are manifestly perigynous. In Gcraniaceae the genus Geranium 

 has the stamens hypogynous, and Pelargonium perigynous. Caryophyllca? 

 are arranged among genera with hypogynous stamens, yet some of them 

 (Larbrea and Adenarium) are perigynous ; in Ulecebrese part of the 

 genera are perigynous, ami part hypogynous. The perigynous 

 stamens of Turneraceae divide them from Cistineae, to which they 

 are closely allied. — The manner in which the stamens cohere is some- 

 times an indication of affinity; for instance, they are monadelphous in 

 Malvaceae and Meliacea?. diadelphous in great numbers of Leguminosae, 

 polyadelphous in Hypericineae ; but more commonly this character is un- 

 important, as in Malvaceae themselves, which have sometimes distinct 

 stamens ; Leguminosae, which have very often such ; in Tcrnstromiaceae, 

 which have both united and disunited ones. — It not unfrequently occurs 

 that the conversion of the petals into stamens takes place imperfectly, in 

 which case a part of the stamens are said to be sterile, and this is sometimes 

 a useful character for detecting affinities. Thus, in many Biittneriaccae 



