20 



ON SEEDLINGS 



they are supported on petioles, as in Microloma (fig. 29), 

 which again are occasionally connate. These differences may 

 occur in very closely allied species ; for instance, in Delphinium 

 Staphysagria (fig. 31) the cotyledons are sessile, while in D. 

 elatum (fig. 30) they are petioled, and in D. nudicaule (fig. 32) 

 the petioles are connate. 





FIG. 43. Seedling of Sapindus 

 incequalis. Half nat. size. 



FIG. 44. Seedling of Rhus Thun- 

 bergii. Half nat. size. 



Generally the cotyledons are entire ; but sometimes cre- 

 nate, as in Cordia (fig. 33), or lobed, as in Pelargonium (fig. 

 34) and Malva (fig. 35). Often they are emarginate, as in 

 Impatiens (fig. 12), Mustard (fig. 3), and Cabbage, Ipomoea 

 (fig. 88), Convolvulus, Galium (fig. 92), Eucalyptus (fig. 38), 

 Pentapetes (fig. 39), &c. They are sometimes even bifid, as 

 in Eschscholtzia (fig. 40) and Ipomrca dasysperma (fig. 89) ; 

 trifid, as in the Cress (Lepidium) (fig. 4) ; or in four long 

 lobes, as in Pterocarya (fig. 41). Sometimes auricled at the 



