384 ON SEEDLINGS 



or most species of Lupinus both before and after germination, 

 including L. mutabilis, L. micranthus, and L. sulphureus. 

 The cotyledons of the latter are also connate at the base. 

 To this type the following agree in all general particulars, 

 namely, Hedysarum neglectum, H. coronarium (fig. 280), 

 Lathyrus macrorhizus, Vicia sativa, Astragalus galegiformis, 

 and Canavalia virosa. 



The seeds of those mentioned vary considerably in size 

 and shape, in the amount of space occupied by the radicle, 

 and the shape of the latter. In Lupinus mutabilis the radicle 

 is trigonous, and in L. micranthus it is flattened and biconvex 

 owing to pressure. In most cases the seeds are laterally flat- 

 tened, and many of them are oblong, while others, such as 

 Lathyrus odoratus, and L. macrorhizus, are globular. Those 

 of Canavalia virosa and Phaseolus multiflorus are notable for 

 their size. A rather exceptional case occurs in Caragana 

 arborescens, where the cotyledons, although normally accum- 

 bent, are often obliquely so, and sometimes even incumbent. 

 The cotyledons are occasionally unequal in thickness. The 

 segments of the lomented fruit of Hedysarum coronarium and 

 others are remarkable for the number of outgrowths or ex- 

 crescences, often hooked, from their surface and sutures. 



The second subgroup includes a considerable number of 

 species the cotyledons of which are more or less indented on 

 one side owing to a thickening or indentation at the hilum. 

 This type may be represented by Clitoria Ternatea (fig. 286), 

 which has a transversely oblong seed. The base of the coty- 

 ledons is also more or less unequal, or cut away on one side, 

 owing to the space being occupied by the radicle as in the last 

 subgroup. Here may be classed Ononis arvensis, Medicago 

 sativa, M. rigida, ^Eschynomene aspera, and Swainsonia 

 galegifolia. 



In all these cases the seeds vary greatly in shape. Those 

 of Ononis arvensis are nearly globular, and covered with small 

 tubercles ; in the species of Medicago there is a special develop- 

 ment of the testa on one side of the seed to accommodate the 

 radicle. The indentation on the side of the seeds of ^Eschy- 

 nomene aspera is so deep as to make them curved or reniform. 

 Those of Swainsonia galegifolia are broadly cordate and 



