A. Gray—istivation and its Terminology. 341 
relating a as it does to the arrangement of a acca of leaves in 
e bud, and evidently quite as pppoe ie a whorl o 
ie ger number of parts than two, i. e.— 
“Obvoluta , quum margines eae posepeeeansietiy oppositi 
folii marginem rectum.” Phil. Bot., 105. Or, in Term. Bot., 
‘pagina superiore peas approximatis ita at: Fo latus 
distinguat alterum foliu 
This, as the by Fete seg and the diagram in the Philosophia 
Botanica show, answers in estivation to mode II It was 
early taken up as such by Mirbel (Elem. Phys. Veg. et Bot., 
1815, li, 738, 739), where the polypetalous corolla of Hermannia 
and ‘Oxalis, and the gamopetalous corolla of Apocynee are 
cited as examples 
alvate xstivation, our mode Ht, is oh ee defined by 
Mirbel i in the same place, and still earlier by B 
inngeus made no use of estivation as a oo racter. Nor 
it was first accurately observed by Grew. In it Brown defines 
Only the valvate mode, “ubi margines folioloruin vel lacini- 
arum integumenti invicem applicati sunt, capsule valvularum 
in modum.” In the body of the work, wherever it is impor- 
hs the Sgigny ats is noted as valvate, imbricate, plicate, indu- 
plicate, &c.; and the open zstivation (aperta) i is named by him 
in ie paper. 
Being the first to em ploy sea systematically, and to 
develop its value, Brown's term nology for its modes may well 
considered authoritative. and so indeed it is, as far as it 
es. But he did not make one pig distinction viz., that 
tween our [ and II. Imbrica n his use, comprises all 
kinds of overlapping, that of the pet of Apocynete and of a 
Gentian, as well as that of a Primrose. He must have not 
Only noticed the “difference, but also appreciated its general 
