of Cowania and Sieversia. 577 



dones spathulatae, piano- con vexae : radicula subulata, coty- 

 ledonibus duple!) brevior, recta, centripeta. 



The habit of this plant, so widely different from that of the 

 species of Sieversia hitherto recorded, led me at first to suspect 

 it might prove a distinct genus ; but after a careful examination 

 of the parts of fructification, I could discover nothing material 

 to confirm my suspicion. A comparison of the description of 

 this plant with Mr. Brown's excellent character of Sieversia, 

 given above, will show how nearly they coincide in every essen- 

 tial point. The other species of Sieversia are all herbaceous 

 plants, with the habit of Geum. 



EXPLANATION OF Tab. XXII. 



Fig. 1. A Branch, of Cowania Mexicana. 

 %. A Leaf, magnified. 



3. Calyx laid open to show the inside of the tube, and the 



situation of the ovaria. 



4. An Achenium surmounted by the persistent Style. 



5. The Embryo — natural size. 



6. The same magnified. 



7- A Branch, oi Sieversia paradoxa. 



8. A Leaf of the same magnified. 



9. Achenium of the same. 



10. Embryo of the same magnified. 



XXIX. De- 



