104 CRUCIFEIUE. 



transversely folded upon themselves, instead of being up- 

 wardly bent upon the radicle at their very base. 



Herb small, aquatic, with a tuft of annual fibrous roots, 

 from which rise clustered terete and elongated-subulate 

 loosely cellular leaves, and naked scapes, bearing a raceme 

 of few and minute white flowers. 



Etymology. Name formed from subula, an awl ; in allusion to the shape 

 of the leaves. 



Geographical Distribution. A genus of a single species, indigenous 

 to the colder parts of the northern temperate zone, growing on the gravelly 

 margins of lakes and pools, where it is ordinarily covered with water. In 

 the United States this little plant has as yet heen detected only in the State 

 of Maine, where it was gathered long ago by Nuttall* and recently by Tuck- 

 erman and by Oakes. Probably it is not local, however, but has escaped 

 notice in the North from its size and the place of growth as much as from 

 its rarity. 



PLATE 71. Subularia aqdatica, Linn. ; — in flower and fruit, of the 

 natural size ; from fresh specimens gathered in Maine and sent by 

 Mr. Oakes. 



1. A magnified leaf, cut across at the base, to show the air-cells. 



2. A flower, magnified. 



3. A sepal ; and 4, a petal, more magnified. 



5. A magnified stamen, back view ; and 6, inside view of the same. 



7. Pistil, magnified. 



8. A transverse section of the same, showing the ovules, &c. • 



9. An ovule, much magnified. 



10. A silicle, magnified. 



1 1 . Same, dehiscent, showing the seeds. 



12. A detached valve of the same, seen obliquely from the inside. 



13. Replum and seeds, with the partition towards the eye ; magnified. 



14. A seed, more magnified. 



15. Same, showing two transverse sections of the embryo at different 



heights. 

 Hi. Magnified embryo, detached entire. 



