442 Rev. S. Haughtou on the General Law of Phyllotaxis. 



as already explained. In fact, the perfect whorl must be consi- 

 dered as made up of two adjacent whorls, the leaves of which, 

 being intermediate, give double the number, or only half the 

 interval between each for the angle of divergence. 



V. Proteacese. 



A very remarkable group of Exogens, the Proteacese, possesses 

 among its number many whorled species, which supply us with 

 numbers additional to those of the Casuarinese. In the family 

 of Casuarinese we found the number 5, which forms so important 

 an clement in the other Exogens ; and in the Proteacese we meet 

 with the number 3, which is only less important. 



1. Lambertia ericifoUa. Swan River. Leaves arranged in 

 whorls of 3, alternate. Branches, flowers, and fruit follow the 

 same law. Divergence — ^. 



As all the species of Lambertia which I have examined follow 

 this law, it will be sufficient to give their names and localities : 



2. L. uniflora. Swan River. 



3. L. multiflora. Swan River. 



4. L. ilicifolia. Swan River. 



5. L. (sp.). Swan River. 



6. L. (sj).). Near Cape Riche, W. Australia. 



7. L. (sp.). Ditto. 



8. L. (sp.). Ditto. 



9. L. (sp.). King George^s Sound. 



10. L. (sp.). Sydney, New South Wales. 



11. L. inermis. Between Perth and King George's Sound. 



Variety with yellow flowers. 



12. L. (sp.). King George's Sound. 



13. L. formosa. New South Wales. 



(Divergence in all cases = ~.) 



14. Brahejum (sp.). Cape of Good Hope. Leaves in whorls 

 of 6, alternate. Divergence = jtj. 



15. B. (sp.) Cape of Good Hope. Leaves and branches in 

 whorls of 8, alternate. Divergence = ^'^. 



IG. B. stellatum. Cape of Good Hope. Three specimens 

 examined, from different collections. In all of them I found the 

 number of leaves in the alternate whorls to be 7, giving thus a 

 divergence of y\. 



VI. EricaceaB. 



In this large and important order of Exogens, the whorled 

 law of arrangement universally prevails, the number of leaves in 

 each whorl being 



3, 3, 4, G, and occasionally 7. 



