18 DIANDRIA. MOWOGYNIA. 



in the warm re,c^ions of India, of Peru, Mexico, and the 

 West-Indies, About 47 species are natives of North and. 

 South America. 



26, COLLINSONIA. L. (Knot-root, Horse 

 weed,) 



Calijc bilabiate, above 3 toothed, below bifid. 

 CoroUa miich longer than tlie calix, somewhat 

 funnel-formed, unequally 5-lobed; the lower 

 lobe longer, lacerately fimbriate (or fringed). 

 Stamina 2, sometimes 4. Seeds 4, 3 of them 

 mostly abortive. 



Leaves large. Flowers in terminal panicles, yellowish 

 or inclining- to violet, with the 2 fertile Stamina ex- 

 tended beyond the corolla, 



bpEciES, 1. C. Canadensis. 2.tubero5a. 3.scabra. 4.ova' 

 lis. 5. anisata 6 pimctuta. E. 7. vcrticillata. 



The C. punctata has 2 barren filaments, and the C, 

 anisata is tetrandroiis. ( \ Norih American genus.) In this 

 genus the stamens are observed alternately to approach 

 the style. 



B. Corolla superior. 

 If ft Flowers complete, 



S.7. CIRCjEA. L, (Enchanter's Nightshade.) 

 Catoshort, 2 parted. Petals 2. Stigma emar^ 

 ginate. Capsule ovate, hispid, 2 -celled, not 

 opening; cells 1 -seeded. 



Herbs; with opposite leaves; flowers alternate, in ter- 

 minal spikes. 



Species, 1. C. lutetiana^ ^ canadensis 2. alpina? Thia 

 does not well agree with the European species. 



ttttt Flowers incomplete, 

 38. LEMNA. L. (Duck-weed.) 



Calix of one entire leaf. Stamens alternately 

 cleveh)ped, seated upon the ovarium at its base; 

 style rylindric, stigma funnel form. Capsule 2 

 to 4 -seeded. 



