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VL. On Gripidea, a New Genus of the Loasaceæ, with an account of some Peculiarities 
- in the Structure of the Seeds in that Family. By Joux Mirks, F.R.S. & L.S., Com- 
mend. Ord. Imp. Bras. Rose. 
(Plate XXVIII.) 
Read April 20, 1865. 
Is the collection of plants from the interior of Brazil, made by Mr. Weir for the Royal 
Horticultural Society, there is a species belonging to the Loasacee so much at variance 
vith others of that family, that it will form the type of a new genus, for which I propose 
le name of Gripidea*. Its chief peculiarities consist in having only five stamens oppo- 
site each of the five larger petals, in the shape of its stigma, the structure of its 
apsule, and the organization of its seeds. Its large scabrid leaves, upon long petioles, 
are opposite, suborbicular, cordate, and divided into five unequal lobes, which are erosely 
denticulated. It has axillary and dichotomously ramified panicles, whose branches are 
furnished at their origin with nearly sessile bract-like leaflets, while a solitary flower 
upon a long pedicel issues from the sinus of each dichotomy. The flowers have five 
larger petals, which are hooded in a peculiar manner; the ovary is almost entirely infe- 
nor, leaving a short pulvinate portion above the segments of the calyx; the style is erect, 
and terminated by a stigma of three linear lobes, broadly fringed on their margins, the 
mary itself being unilocular, with three somewhat spiral, longitudinal, sessile, placenti- 
ferous lines, upon which numerous ovules are crowded. The capsule, of thin chartaceous 
texture, is of a long cylindrical shape, somewhat narrower towards the base, and is crowned 
Mith the persistent reflected leaflets of the calyx, the pulvinate cap, and the remnant of 
the style: it is marked by numerous spiral nervures, and finally splits into three ribbon- 
shaped helical valves, that remain joined together at the summit and base, and which 
ar on their margins numerous small and almost scobiform seeds. 
| From these characters it will be seen that the genus belongs to the section Helicte- 
ow differing from most of the genera of that section in its adnate parietal placentæ : 
respect it approaches Scyphanthus ; but the latter genus has a far more attenuated 
“psule, Which opens by three teeth in the apex, and finally splits into three linear straight 
— valves, which separate also at the top, and thus become entirely free ; the two 
their are likewise at variance in the nature of their seminal integuments, the form of 
| embryo, the shape of their petals, the number of their stamens, in their stigma, the 
| of their inflorescence, and in their general habit. - ; T— 
Mthough Caiophora agrees with it in its capsule, which bursts along its mites into 
his Spiral valves, adhering t í ities, it is at variance with it in the 
NIU. ias together at their extremi aes uini 2-3 viii 
OF its stamens, in its stigma, but more especially in its ——À S 
* x ; à 
From ypimos, rete, eidéa, forma, because of the retiform covering of its seeds. : 
I 
