64 Etiphorbiaceae, Callitrichaceae 



sepals or twice as many or co or i. Carpels usually (3). 

 Fnut usually a capsule splitting into three mericarps. 

 Endospeinn copious. 



Subfamily Crotonoideae, Each carpel with one 

 ovule. 



Tribe i. Acalypheae. Latex absent. Calyx valvate. 

 Flowers racemose. ^ usually without corolla. 



Only British genus : Mercurialis. 



Tribe 2. Eitphorbieae. Latex present. Flowers in 

 cyathia\. ^ without corolla and usually without calyx, 

 and with only one stamen. 



Only British genus : Euphorbia. 



Suborder 4. Callitrichineae. Characters of the 

 family. (Systematic position doubtful. Possible affini- 

 ties with Verbenaceae.) 



Fam. 6. Callitrichaceae. Slender glabrous herbs, 

 often submerged. Leaves opposite entire, upper often 

 rosulate and floating. Flowers monoecious, naked, often 

 with two falcate bracteoles. ^ of one terminal stamen. 

 J of two transverse carpels. A longitudinal septum 

 makes ovary 4-I0C. Fruit of four drupaceous mericarps. 

 Seeds with endosperm. 



Only genus : Callitriche. 



Order 15. Sapindales. Mostly woody plants. 

 (Impatiens is the only British herbaceous genus.) 

 Characters of Geraniales but ovules in the reverse 

 position, either pendulous with dorsal raphe and micro- 

 pyle directed upwards, or ascending with ventral raphe 

 and micropyle directed downwards. 



+ A Cyathium is a condensed cymose inflorescence resembling 

 a single flower. 



