24 ON SEEDLINGS 



hypocotyl being very short or undeveloped and subterranean. 

 The long petioles carry the lamina up to the light, and their 

 union gives strength or rigidity while the material necessary 

 for the production of two strong petioles is economised. This 

 type is well represented by Smyrnium perfoliatum (fig. 408). 

 The combined petioles strongly resemble a slender, terete 

 hypocotyl, and while we are expecting to see the plumule 

 emerge from between the free portions, a leaf makes its 

 appearance from the soil. Examination shows that it pro- 

 ceeds from a cleft at the very base of the united petioles and 

 directly abutting upon the hypocotyl which soon becomes 

 fleshy and tuberous in its nature. The first leaf has a tri- 

 partite lamina. During the germination of the embryo 

 the broad cotyledons are able to make their exit from the 

 globular concave seed by the splitting of the crustaceous 

 exocarp. Both this species and S. rotundifolium have 

 emarginate cotyledons, and they, together with S. Olusatrum, 

 closely agree in all main particulars. Ferula foetida and F. 

 communis may be placed here because their petioles are 

 connate at the base. The petioles with the linear-lanceolate 

 lamina of the former measure about 14 cm. long ; but the 

 petioles are connate for a distance of 8-10 mm. only. The 

 first two leaves have a tripartite lamina. The cotyledons of 

 F. communis are very much shorter, trinerved, linear ; and 

 the petioles are connate for 7-8 '5 mm. at the base. The first 

 leaf is bi- to tri-pinnatisect. The long narrow cotyledons do not 

 correspond with the large oval or elliptic dorsally compressed 



In the fourth group may be included all those species 

 having linear petiolate cotyledons of moderate length, as 

 represented by Bupleurum fruticosum. The first four leaves 

 are obovate, the ultimate ones oblong-obovate. B. longifolium 

 and B. falcatum agree in all respects except in having narrower 

 leaves. The species belonging to this genus are remarkable 

 amongst the Umbelliferse for their entire leaves. Other species 

 agreeing with the above in respect of the cotyledons are 

 Ammi glaucifolium (fig. 409), Chaerophyllum aureum, Carum 

 Carvi, Ptychotis Ajowan, and Daucus Carota. Ammi 

 glaucifolium shows well-marked evolution of the leaves, the 



