482 



NATURAL HISTORY OF PLANTS. 



Proserpinaca ^ (fig. 468-471) also consists of aquatic herbs. The 

 leaves are alternate, entire, dentate or pectinate and pinnatifid, like 

 those of MyriophyUon, The flowers ^ are hermaphrodite, axillary, 

 solitary or grouped in cymes ; they are often trimerous or more rarely 



tetramerous, and differ from those of the 

 preceding genera by two principal charac- 

 ters : the petals are wanting, and the 

 stamens, superposed to the sepals, are the 

 same in number as the latter and reduced 



Proserpviaca paluntris. 



Fig. 469. Flower 



Fig. 470. Long, 

 sect, of flower. 



Fig. 471. Fruit. 



to a single verticil. All the other im- 

 portant traits of their organization are 

 those of Haloragis, Thus, the floral re- 

 ceptacle is concave, bell-shaped, and its 

 cavity is filled by the adnate and inferior 

 ovary, the cells of which, three or four in 

 number, contain each a descending ovule, 

 with micropyle interior and superior. On the margin of the recep- 

 tacle are inserted epigynously the sepals, which are valvate, and the 

 superposed stamens, the filaments of which are short and erect and 

 the anthers basifixed. Two species ^ are known, from the Antilles 

 and North America. 



Fig. 468. Floriferous and 

 fructiferous branch.. 



YI. GUISFNEEA SEEIES. 



Gunnera'^ (fig. 472-475) has polygamous or monoecious flowers. 

 In those which are hermaphrodite (fig. 475) and generally dime- 



^ L. Gen. n. 102. — J. Gen. 68 ; Ann. Mus. iii. 

 320, t. 30.— Lamk. ///. t. 50.— Pom. Diet, viii. 

 117 ; Suppl. V. 369.— DC. Prodr. iii. 67.— Endl. 

 Gen. n. 6137.— B. H. Gen. 675, n. 5.— H. Bn. 

 Payer Fam. Nat. Z11. — Trixis Mitch. Eph, Cur. 

 Nat. (1748) n. 23, c. ic— G^rtn. Fruct.i. 115, 



t. 24 (not P. Br.). 



2 Small, greenish, or brownish. 



3 ToRR. et Gr. Fl. N.-Amer. i. (1840) 528.— 

 A. Gray, Man, ed. 5, 175. 



^ L. Mantiss. 16, 21 ; Gen. n. 1272 ; Amcen. vii. 

 495.— J. Gen. 405, 452.— Lamk. Diet. iii. 61 ; 



