Mr D. Don on certain Genera in the Flora Perutnana. 113 



Ovarium pediccUatum, ovatum, compressum, uniloculare: ovu/w pluri- 

 bus. Styhis brevissimus, glaber. Stigma simplex, truncatum. Capsuia 

 pedicellata, compressa, triangularis, truncata, unilocularis, bivalvis, de- 

 casperma : valvis navicularibus, in angulum prominentem productis 

 (compressione cauli contrario), quasi transversis : suturcB inUs magis 

 prominulae, funiculi3 umbilicalibus, complanatis persistentibus instructae. 

 Semina simplici gyro cochleata, extremitatibus connatis ! umbilico in 

 sinu; testa exterior Crustacea, laevis ; inferior cartilagineo-membranacea: 

 albumen nullum. Embryo flexura arcta teres, luteus: cotyledonUms in- 

 cumbentibus, semicylindricis : radicula his pariim longiore, basi acuttL 

 Planta (Mexicana) suffruticosa, procumbens^ glaber, glatKo-virens. Caules plu- 

 rimij teretes, ramosissimi. Folia alterna, petiolata, temata : foliolis breviter 

 stipitatisy cuneiformibus, retusis cum mucronulo rejlexo, integerrimis, 3—4- 

 linearibus. Petioli semicylindrici^ 3—6 lineas longi. Stipulae 2, setacece, 

 brevissimcB. Flores aanllaresy solitarii, pedunculati, albi, Pedunculi «tt6- 

 capillares, semipollicares* 



1. C. mexicana, 



Cleomella mexicana, Decand. Prod. 1. p. 237. 



Cochlearia trifoliata, Sesse et Mocinno MSS. 



Hab. in Mexico. Sesse et Modnno* % (V. s. sp. in Herb. Lamb.) 



A genus first proposed by my candid and learned friend 

 M. De Candolle, in the second volume of his Prodromus Sys- 

 iematls Naturalis Regni Vegetabilis, where the essential cha- 

 racters are given ; but I have thought that a detailed descrip- 

 tion, derived from the examination of several complete speci- 

 mens, might be desirable, especially as it is probable M. De 

 Candolle had not an opportunity of seeing specimens of it, but 

 had derived his knowledge of the genus from the unpublished 

 drawings of the Flora Mexicana. This genus is interesting, as 

 exhibiting, both in its habit and structure, an evident affinity to 

 the Tropaolea, which I have elsewhere proposed to place near 

 to Cruci/erce and Capparidece. The BalsaminecB^ which I 

 also formerly proposed to add to this class, I am now fully per- 

 suaded must be arranged near to Violece — to which, even in the 

 nervation and dentation of their leaves, they exhibit a closer 

 affinity. The placentae in Cleomella are very prominent, and 

 extend sometimes considerably within the capsule, constituting 

 a sort of partition ; and as the rudiment of a connecting mem- 

 brane, analogous to the dissepiment in Crucif'crce, is occasion- 

 ally observable in the young ovarium, it is probable that that 

 organ is wholly absorbed in the very early stage of the ovarium, 

 in Capparidece. 



OCTOBER — DECEMBER 1830. H 



