8o HELIANTHEMUM CAROLINIANUM. CAROLINA SUN ROCK-ROSE. 



in the " Plora of North America," are not sure of it; and Wood 

 makes no distinction between it and tliose which have the sepa- 

 rate forms of flowers/== Mr. Charles Darwin enumerates many 

 plants which are now known to have two forms of flowers. 

 These apetalous ones are arranged for self-fertilization, while the 

 brighter flowers admit of a possible cross by the pollen of a 

 strange flower; and this he regards as an argument in favor of 

 the advantages of cross-fertilization, as for mere propagation the 

 self-fertilizing forms of flowers would be sufficient. It is remark- 

 able that, although the elder Darwin should refer to the motion 

 of the stamens in Cisius, and the two forms of flower are well 

 known to American Botanists, the eminent grandson should have 

 wholly failed to notice the plant in his curious work. It will be 

 well worth the while of the student to watch the behavior of 

 these flow^ers, and indeed of the whole plant. There are too 

 many who are content to repeat what others have written rather 

 than to observe for themselves, and in this way errors are often 

 perpetuated. Thus in our plant "Citizen Ventenat," who in the 

 (French) year 8 wTote an account of the new plants growing in 

 the tT-arden of "Ciuzen Cels," tells us it was raised from seeds sent 

 from Charleston, South Carolina, by Bosc, and that it has "fibrous 

 roots;" and this statement has been repeated often since. But 

 the reader will note by our drawing that the roots are rather 

 fleshy than fibrous. With a very litde more expansion they 

 would be tuberous. 



* As this chapter is going through the press, it may be added, as an ascertained fact, that 

 Wood is correct. This species has sometimes cleistogene flowers. 



Explanations of the Plate. — i. A complete average-sized plant. 2. Nearly mature capsule 

 magnified, and cut across to show the three valves characteristic of the genus. 



