E UP HOBBIA OE^. 



151 



VIII ? CALLITEIOHE SERIES. 



Callitriche'^ (fig. '254-258), wMcli lias been considered, not with- 

 out question, as a lessened aquatic type of biovulate Euphorbiaceae, 

 has hermaphrodite or more frequently monoecious or dioecious, dime- 

 rous apetalous flowers. The male flower has two lateral imbricated 



. Callitriehe stagnalia. 



Pig. 257. Fruit (f). Kg. 255. Male Fig. 254. Florife- Kg. 256. Female 

 monandrous flower (f). rous tranch. flower (4). 



Kg. 258. Long, 

 sect, of fruit. 



sepals,^ and two alternate stamens inserted upon a small convex recep- 

 tacle or even only one middle stamen. The filaments are free,, erect, 

 exserted at anthesis ; the anthers are reniform, dehiscing by a semi- 

 circular lateral cleft '. In the female flower the perianth, some- 

 times but little developed, is similar to that of the male flower, and 

 the gynseceum is composed of a free ovary,* with four cells super- 

 posed to the sepals, each divided into two half cells by a false centri- 

 petal partition, surmounted by a 'style soon divided into two simple, 

 straight lateral branches, stigmatiferous on their whole surface. In 

 each cell is found two collateral, descendent, anatropous ovules, 

 with micropyle directed upwards and outwards, the exostome 

 thickened and often surmounted by a small cellular obturator. In 

 the hermaphrodite flowers there is an ovary with two cells superposed 

 to the sepals, and one or two alternate stamens. The fruit is cap- 

 sular, with two rather thin shells, each divided into half shells, 

 marginate or winged at the back by deduplication of the false par- 

 tition. In each half shell is found a descendent seed with an 



1 Cfen. n. 13. — ^Adans. Fam des PI. ii. 471. 

 — J. Gen. 19. — Lamk. Diet. i. 664; Suppl. 

 ii. 36.— a^RTN. Frnct. i. 330, t. 68— DC. 

 Frodr. iii. 70. — Nees, Gen. ii. 4. — ^Endl. 

 &m. n. 1830.— H. Bn. in Bull. Soc. Bot. de Fr. 

 V. 337; Fuphoriiac. 660, t. 21. iig. 28-33.— 

 Claeke in Trans. Idnn. Soc. xxii. 411; in 

 Seem. Journ. of Bot. (1865), 36. — Hbqelm. 



Monogr. der Gatt. Callitriehe. Stuttg. (1864). 

 — B. H. Gen. 676, n. 9. 



2 Botanists who consider the flowers naked 

 call these bracts. 



•■• There are certainly two oeUa, the clefts 

 heing confluent at the summit. 



^ It has been supposed "adherent,'' with a 

 calyx having an abortive limb. 



