and the Pyrenees, in 1825. 245 



less green ; while in H. canum, they are white and hoary. But 

 what, then, becomes of the intermediate H. italkum, which par- 

 takes of both these characters * ? 



" Of Helianthemum Jumama and procumbens we also laid 

 up a few specimens to-day. Dunal is certainly right when he 

 adds the remark, that perhaps H. ericoides is but a variety of 

 H. Jumama : it is no doubt a very distinct variety, but has no 

 claims to be ranked as a species, nor does it appear to differ in 

 the least degree from var. u of H. Jumama : may not even var. y 

 be joined to var. a, ? Further, on what good grounds is H. pro^ 

 cumhens to be separated ? Dunal rests upon the property of 

 the seeds -[- remaining attached to, or being discharged from the 

 opened capsule ; but we have assuredly found both on the same 

 plant, and as to habit there is little diiterence. 



" Few who find Cisti and Helianthema together in the wild 

 state, would, I think, presume to unite the two genera ; yet 

 there does exist a species which tends to ally them most inti- 

 mately. I allude to the old Cistus libanotis. Now, it is diffi- 

 cult to say to which genus this should be referred, by judging 

 only of the habit. Nay, there seem to have been two distinct 

 species confounded together, but which Dunal has properly se- 

 parated : the one has the capsule of a Cistus, the other of a 

 Helianthemum; th^y differ in no other respect. Dunal has 

 called the one C. Clusii, the other Helianthemum libanotis. In 

 both, the styles are shorter than the stamina, and the calyx tri- 

 sepalous. To H. libanotis, Dun. certainly belongs Cistus caly^ 

 cinus, Linn. This synonym is adduced by Willdenow under 



* The Helianthemum canum^ Dun. I believe to be the C. canus of Linnteus ; 

 but Sir J. Smith says that Linnaeus's plant is very diiFerent from his C. mari' 

 foliics, whereas Duhal's H. canum is so closely allied to it, that there is scarce- 

 ly either a natural or artificial character by which it is to be separated. As 

 to Dunal's //. marifolium, it certainly differs from the British C. manfolius, 

 with which, however, De Candolle's plant (from Switzerland) entirely accords. 

 There are thus three species : Hel. canum of Dunal and Linn. ; H. mari/olium, 

 DC. and Lann. ; and Dunal's H. marifolium. * 



f My friend M. Guillemin has recently discovered, that, in the end of the 

 broad and narrowed Helianthemum, there exists two different structures of the 

 embryo. 



JANUARY — MARCH 18^7. R 



