EUPHORBIACEyE 473 



axils leafy branches. The cotyledons of Petalostigma quadri- 

 locularis are larger and taper slightly at the base into hairy 

 petioles, but are otherwise similar to those of the last species. 

 The leaves are considerably smaller, oval and hairy. The 

 cotyledons of Phyllanthus mucronatus are very similar to those 

 of its congener mentioned above. The first four leaves are 

 smaller and obovate. The cotyledons of Euphorbia hetero- 

 phylla also conform to this type. Those of E. platyphylla 

 slightly depart from it in being wider at the base, oblong-ovate, 

 and alternately penninerved. The two primary leaves are 

 small and obovate. The cotyledons of Mercurialis annua 

 are similar, in being broadly oblong-ovate, but trinerved in 

 the lower half. The first pair of leaves are comparatively 

 large, ovate, serrate and thinly hairy. 



The cotyledons of Euphorbia splendens (fig. 638) are more 

 nearly orbicular than those of any other species in the Order 

 coming under my observation. They are also entire or rarely 

 slightly emarginate and obscurely trinerved. The first three 

 leaves are elliptic, finely acuminate and closely penninerved 

 with the nerves incurved. The hypocotyl becomes fleshy and 

 tapshaped while the seedling is yet quite small and has de- 

 veloped but a few leaves. Probably the succulent and leafless 

 species would even be more notable in this respect. During 

 germination the seed is frequently carried up on the cotyle- 

 dons, and their growth as well as the swelling endosperm 

 cause the crustaceous testa to split along the greater part of 

 its length exposing the endosperm which continues to cover 

 the cotyledons for some time till mostly absorbed. The same 

 or much the same thing occurs in E. Peplus and also in 

 Eschscholtzia amongst the Papaveracese. 



The cotyledons of Acalypha virginica are orbicular, widely 

 and shallowly emarginate, and trinerved with the primary 

 nerves much branched. The first pair of leaves are opposite, 

 widely and shallowly crenate. The cotyledons of Dalechampia 

 capensis (fig. 645) are also orbicular, sometimes oblong, but 

 they are very subject to malformation, in being undulated, 

 erosely emarginate, often oblique or irregularly cut away at 

 the base, or elsewhere, and variously twisted. 



A number of species having more or less succulent or fleshy 



