COMPARATIVE ANATOMY OF THE CÜCURBITACE^. 15 



The pnrencliy matous cells in the rhizomes are remarkahly 

 large as compared with those of the ordinary stems on account 

 of tlieir reserved starch-grains. On the epidermis of the rhizomes 

 stomata and trichomes are also sometimes found. 



The large starch-grains found in the rhizomes are of tlie 

 following sizes : 



BianiPtor. 



Gymnostemma cissoides 0.060 mm. 



3IeIothria japonica 0.034 „ 



Those of the former plant (PI. II. Fig. 38) are the largest 

 among the starch-grains contained in any organs of the Cucur- 

 bitaceae. 



CHAPTER II. 



THE HYPOCOTYL. 



The germinating plantlets of the Cucurhitaceœ have long 

 terrestrial hypocotyls or very short subterranean hypocotyls. 

 Aclinostemma racemosum, Melothria japonica, ^Schizopepon bryo- 

 niœfolius, var. japonicus, Jfomordica Charantia, Lniffa cylindrica, 

 L. acutangula, Citrullus vulgaris, Cucumis sativus, C. 3Ielo, 

 Benincasa cerifera, Lagenaria vulgaris, and Oucurbita Pepo, have 

 the former kind ; while Trichosanthes cucumeroides, T. japonica, 

 T. multiloba, and Gymnostemma cissoides, have the latter. 



Contour. As seen in a transverse section the contour of the 



