275 able to experiment v/ith, I think thet choree ters derived from the 

 mode of development of seedlinc-s should not be neglected, as they 

 sometimes may show or confirm the supposed relationship of two 

 differen"*- i?-enera . For example, when describin,'? the g'enus ^^irasria 

 that v;iii BPT^ear later on in these articTes I had judged its rele- 

 tionshin to be near that of the genus Llthops, and when the few 

 seedlinrs I was able to raise of it. developed, this view was con- 

 firmed, -"or I found that their manner of development from the cotj- 

 ledonary to the pdult stage is the seme as that of the genera 

 lithons ?nd Conophytum and not all like that of ^"esembrypnthemum 

 and most other- genera that I have been able to experiment ^'ithi 

 thus eddinp- a further character whereby it is distinguished from 

 these genera. 



As previ^ously stated, J do not propose her to divide the 

 vrhole e-enus i-es-embryanthemiim as now constituted into separate 

 ^ener- , nor to re-define its sections as I think thej'' ought to be 

 defined, because - have not acces to, nor can I obtain, the mater- 

 ial necessary for this purpose, fruit and seed, and often suffici- 

 ent flowers "for dissection be^np absent. Kor do I v/ish intimate 

 that T think everv frroup into which the genus is now di-?ided should 

 constitute a genus. 3iit I do think, as -""^aworth over one hundred 

 ^'•eprs ago str"ted, the t severe 1 among them are undoubtedly good 

 generr , and I here pronose to sepr rote and charecterise ss distinct 

 ?enerp some of the groups of which I have been able to examine 

 living Plants or aceouate dried material, and thus hfve assured my- 

 se"""^ thpt they undoubtedly differ in structure and habit from the 

 main characters assigned to the genus by Linne. I'iost of the genera 

 described beloi^ pve easily recognised at sight when out of flov/er 

 by their hrbit alone, when once they are knov.'n, an advantage not 

 possessed by the majority of genera in other Natural ^rders. 



Therefore, in constructing the key to the genera given below, 

 I ha""'e considered vegetative characters (next to fruit characters) 

 as 0:^* first importance, because they pre always associated with a 

 distinct florei end "^ruit structure, and are always present, while 

 ■^lo^ver and fruit are not slways obtainable. 



In writing O"*" these plant I have also endeavoured tc the 

 descriptions so that the""' cen be understood hy the averege gardener 

 as v^ell as by the botanist, because I reelise that there are 

 large numbers vjho cultivate these plants that have no means of iden- 

 tifying any of them, and therefore these articles, if very carefully 

 studied, vfiay be of some heir to those who have not eccess to the 

 r'^re books in which these plants are figured and described, ^^t 

 the same time it is impossible for me to here deal with all the 

 kno^"n species, or even with all thpt are in cultivation, but in 

 meny c«ses I have given descriptions of some or ell the chief spe- 

 cies known or in cultivption, in others I can only enumerate them, 

 anc^ in the case of the vast genus '^^-esembryanthemum onlj'' e selection 

 of s fev7 kinds can be made. 



N. E. Brown 

 (To be! continued.) 



MSSSI.IBHYAlTTHEI,'irai, 

 Osrd. Ghron. HI. 78 s 412. 1925, 

 Glontinued from page 273. 



412 K3Y TO THE GSNERii, 



