388 ON SEEDLINGS 



their basal end in the seed, thus occupying the space that 

 would otherwise be appropriated by them. Lupinus arboreus 

 (fig. 264), L. elegans, L. micranthus, and others represent 

 this type. The cotyledons are generally petiolate; but in 

 L. linifolius they are subsessile and strongly falcate, being 

 quite exceptional. A more unusual case occurs in L. sul- 

 phureus (fig. 265) and L. recurvatus, where the cotyledons 

 are strictly sessile and connate along the whole of their basal 

 edges. Those of the former are suborbicular, and the peculiari- 

 ties exist while the embryo is still in the seed. The leaves of 

 the various species of Lupinus are digitately compound from 

 the first, with linear or lanceolate leaflets varying greatly in 

 number. 



Tribe Trifoliea. As far as shape is concerned, the leading 

 type of cotyledons is the prevalent one in this tribe; they 

 are usually small and narrowly oblong. The first leaf is 

 simple or consists of one leaflet, while succeeding ones are 

 pinnately trifoliolate. To this tribe belong Pocockia cretica, 

 Trigonella corniculata, T. gladiata, Medicago maculata, M. 

 orbicularis (fig. 271), Melilotus ofiicinalis, M. parviflorus, M. 

 albus, M. leucantha, Trifolium Boissieri (fig. 272), T. repens, 

 T. redenakum, T. minus, T. subterraneum, and others. The 

 lamina of the cotyledons is often articulated with its petiole, 

 notably in the species of Trigonella, Melilotus, and Trifolium. 

 A slight departure from the above type is met with in Ononis 

 Natrix (fig. 270) and 0. ornithopodioides, where the cotyledons 

 are broadly oblong or broadly ovate and hairy, or glandular- 

 pubescent. The first three leaves of Ononis rotundifolia and 

 first four of 0. ornithopodioides and 0. Natrix are simple, 

 while those that succeed are pinnately trifoliolate ; but these 

 numbers may vary in different individuals. The cotyledons 

 of Trigonella Fcenum-graecum are chiefly notable for their 

 size. 



Cases of severe competition amongst the seedlings of a 

 single fruit occur in species of Medicago where the indehiscent 

 spirally coiled pod contains a large number of seeds. This is 

 well represented by M. orbicularis. 



Tribe Loteee. A few cases occur in this tribe, as in the 

 Genisteae where the cotyledons are falcate, as in Lotus biflorus, 



