152 CLASSES OCTANDRIA AND EXNEANDEIA. 



with four pistils known in the class Ileptandria ; its common 

 name is liz^Yirs-tail {Sauru?nis). It. has arrow-shaped leaves, 

 ilowers destitute of a corolla, and growing upon a spike ; it is to 

 be found in stagnant waters. It gives name to the natural 

 order Saururaceoe ; the Ilowers of which are achlamydeous^ or 

 without perianth. The number of stamens sometimes varies. 



204. Order Heptcujynia^ seven 2yistils. — ^The Septas, a native 

 of the Cape of Good Hope, is considered as the most perfect 

 plant in this class, though its natural affinities are obscure ; it 

 has seven stamens, seven j^istils, seven petals, a calyx seven- 

 parted, and seven ovaries (one to each pistil), which become 

 seven capsules, or seed-vessels. 



205. Ileptandria is the smallest of all the classes ; we do not 

 find here, as in most of the artificial classes, any natural families 

 of plants ; but the few genera which it contains differ not only 

 in natural characters from other plants, but they seem to have 

 no general points of resemblance among themselves. 



LECTUEE XXYIII. 



OCTANDRIA, EIGHT STAMENS. ENNEANDRIA, NINE STAMENS. 



206. The eighth class, although not large, con- 

 tains some beautiful and useful plants. In the 

 order Monogynia is the (Enotliera^ or evening prim- 

 rose^ many species of w-hich are common to our 

 country ; some grow to the hight of five feet. The 

 flowers are generally of a pale yellow, and in some 

 S23ecies they remain closed during the greater j)art 

 of the day, and open as the sun is near setting. 



a. Tills process of their opening is very curious ; the calyx sud- 

 denly springs out and turns itself back quite to the stem, and the 

 petals beuig thus released from the contmement in which they had 

 been held, immediately expand. There are few flowers which thus 

 hail the setting sun, though many salute it at its risiyig. The 

 flowers of the QEnothera are thickly clustered on a spike, and it is said tha 

 " each one, after expanding once, fades, and never again blossoms." This flowt 

 has been observed in dark nights to throw out a light resembling that of phos- 

 phorus. TIjc regularity of its parts renders it a good example of the eighth class; 

 the different parts of its corolla preserve in their divisions the number four,- or half 

 the number of stamens. It has four large yellow "petals ; the stigma is four-cleft ; 

 capsule four-celled, four-valved ; the seeds arc aflixed to a four-sided receptacle. 



207. The (Enothera belongs to the natural order Onagror 



203. Faururus.— 204. Order Heptagynia.— 205. Remarks upon the class Heptandna.— 206. Eighth 

 class — Evening primrose — a. Process of opening, &c. — 207. Natural order, Onagraceie. 



