STRUCTURE.] THEIR NUMBER AND ABSENCE. 63 



first of those which surmount the outer mass,, and subse- 

 quently of the divided termination of the central subulate 

 body. As this latter increases in length, it is seen to termi- 

 nate in a green convolute leaf, in the axilla of which is placed 

 another very rudimentary one. At this period the extremity 

 of the subulate body next the hilum has also become exserted, 

 and forms a subulate fleshy and undivided projection. Into 

 this the cellular tissue of the fleshy body passes, although 

 there is a faint line of demarcation between the two. 



" The absolute nature of the outer fleshy part," Mr. Grif- 

 fith observes, "can only be determined by pursuing the 

 development of the ovula. The nature of the subulate body 

 is evident ; it is the root, the true plumula being the minute 

 scaly body at its distal end. The root points, as it should do, 

 towards the side of the hilum, the situation, in fact, of the 

 foramen. At the collar it is continuous with the plumula, 

 and laterally with the outer fleshy mass ; which ought, there- 

 fore, to be cotyledonary, and taking it to be so, might be 

 explained, by supposing the cotyledons to be affixed in a 

 peltate manner, and united into a solid mass." 



In number the cotyledons vary from two to a much more 

 considerable number ; four occur in Borageworts, Crucifers, 

 and elsewhere ; in Conifers they vary from two to more than 

 twelve. 



Instances of the absence of cotyledons occur, 1 . in Cuscuta 

 (Plate VI. fig. 19.), in which they may be supposed to be 

 deficient, in consequence of the absence of leaves in that 

 genus; 2. in Butterworts (Lentibulariacese) ; and, 3., in 

 Cyclamen, in which the radicle enlarges exceedingly. To 

 these a fourth instance has by some been added in Lecythis, 

 of which Richard gives the following account : The kernel 

 is a fleshy almond-like body, so solid and homogeneous that 

 it is extremely difficult to discover its two extremities until 

 germination takes place : at that period one of the ends forms 

 a little protuberance, which subsequently bursts through the 

 integuments of the seed and extends itself as a root; the 

 other end produces a scaly plumule, which in time forms the 

 stem. The great mass of the kernel is supposed by Richard 

 to be an enlarged radicle. I, however, see no reason for 



