28 ON THE GENUS ERIOGONUM, 



ERIOGONUM. 



i 



Artificial Class and Order. 



ENNEANDRIA TRIGYNIA. 



Generic Character. 



,Calyx subcyathiformis, basi tubulosa^ liiribus scxfidus 

 inasqualis, extus villosus. Corolla nulla, semen unicum, 

 triquetrum, immarginatum, calyce tectum. (Flores iu- 

 volucrati. Stipula nulla.) 



Observation, — Mode of growth proliferous; stems, 

 leaves, and flowers , persistent; with an imperfect pros- 

 trate or cespitose stem or x^audex, the peduncles or 

 scapes then umbelliferous; when with a distinct stem, 

 erect, and dichotomous; leaves connate and verticillate, 

 on the caudex alternate, always more or less tomentose. 

 Flowers upon articulated peduncles, produced in cup- 

 shaped, campaiiulate involucres, the involucri many flow- 

 ered, simply producing flowers or pe iluncles mixed with 

 setaceous appendices, which are simple or plumose, Calix 

 unequal, 6-parted, subcyathiform, externally villous, 

 covering the seed, the 3 exterior segments reflected in 

 the fruit. Stamens 9, filaments villous at the base, longer 

 than the calyx, disposed by 3s, (as in Rheum) on the 

 base of the larger calycine lacinias; base of the calyx tu- 

 bular to the circular articulation. Styles 3, simple, ob- 

 tuse, long as the stamina, villous below as well as the 

 germ. Seed acute or obtuse triangular, acuminate above, 

 VfX. length, in germination, bursting below, seed com- 

 pressed? ovate, acute. Peri sperm small, farinaceous; 

 Corculum inverted. Seed-lobe^ erect, fiat, oboval; radi- 

 Cjle straight, exserted. 



