ESTIVATION AND ITS TERMINOLOGY. 57 



as in Pfdox, give an appearance like that of twisting, although there 

 is no twist or torsion. But it is to just such cases, in which there is 

 most of seeming twisting on account of the strong convolution, that 

 the term convolute is now and then assigned in the " Prodromus "; as 

 in the character of BtjttneriacecB, and that of Malvaviscus. The latter 

 may perhaps be explained by the peculiarity that the petals do not 

 uncoil in antithesis. But m ApocynacecB, in the "Prodromus," the 

 terms convoluta and contorta are seemingly employed synonymously, or 

 nearly so (the latter most frequently) ; at least I see no difference 

 between the aestivation of Allamanda, said to be contorted, and that of 

 Vinca (rosea), said to be convolute. Endlicher in this regard follows 

 the "Prodromus." In the new "Genera Plantarum " by Bentham 

 and Hooker this mode is most commonly designated as contorta, some- 

 times as contorto-imhricata, rarely {Philadelphus, &c.) convoltda. I 

 have myself, from a period as early as 1840, employed the term 

 convolute, thinking it un advisable to have two names for the same 

 thing, and wishing to restrict, if it might be, the term contorted to 

 cases of torsion. Adrien de Jussieu, on the other hand, used convolute 

 (with strict Linna^an propriety) for regular imbrication with a high 

 degree of overlapping, thus giving two names to different degrees of 

 the same thing. 



It being conceded, I presume, that the mode II. should be 

 specifically distinguished, what name, on the whole, ought it to bear? 

 If we follow prevalent usage, contorta will be the term. But this 

 term was unknown in this sense to the founders of aestivation, 

 Linnaeus and Brown ; it correctly expresses the real state of things 

 in only a few cases ; and where there is torsion, it leads to a most 

 awkward way of expressing it. We have to write, ''lobes of the 

 corolla contorted and twisted: coroUce lohi contorti et torti,^^ intro- 

 ducing dextrorsmn ot sinislrorsum,'^ to express the direction of the over- 

 lapping and of the torsion, which are not always the same. So that 

 the most current name is the least appropriate. Convoluta is as good 

 a name as can be, and its use in the present sense is not unconformable 

 with the Linnaean use in vernation. When well carried out, three or 

 five or more petals, as the case may be, are simply rolled up together. 

 When the overlapping is slight, there is simply the tendency to con- 

 volution. But if, as in other nomenclature, priority gives a paramount 

 claim, obvoluta will be the proper term, beginning as it did with 

 Linnaeus for vernation, and taken up, as it was very early, by Mirbel 

 for aestivation. The only objections to it are, first, that it has never 

 come into systematic use, and, second, that ob, in the composition of 

 botanical terms, commonly stands for obversely or inversely. But 

 obvoluta is not burdened with this signification : it is classical for 

 " wrapped round," as is convoluta for rolled together. I conclude that 

 one or the other of these two terms ought to be used. 



Finally, although there is little, if any, practical misuse, there is 

 some mis-definition, of the term imbricate as applied to aestivation. 

 Adrien de Jussieu defines it well (in " Cours Elementaire," 308) in the 



* 1 note with satisfaction that Bentham and Hooker use these terms to signify 

 from left to right, or from right to left, of a person supposed to stand outside 

 of the closed bud, which is surely the natural position of the observer. 



