COMPARATIVE ANATOMY OF THE CUCUKBITACEiE. 7 



Tn'cJwmes. The trichomes on the stems are multiceUular in 

 every case, and may be divided into four classes : (i.) sharp- 

 pointed conical trichomes, (ii.) blunt-ended conical trichomes, (iii.) 

 short-stalked glandular trichomes, and (iv.) long-stalked glandular 

 trichomes. The first kind is found in Melothria japonica (PI. I. 

 Fig. 5), Citrullus vulgaris^ Cucumis sativus, C. Melo, Benincasa 

 ceriferay Lagenaria vulgaris, and Cucurbita Pepo ; the second, in 

 Actinostemma racemosum, Schizopepon hryoniœfolius, var. japonicus 

 (PL I. Fig. G), Momordica eharantia, Luffa cylindrica, L. acut- 

 angula, Lagenaria vulgaris, Tt'ichosanthes cucumeroides, T. japonica, 

 T. multiloha, and Gymnostemma cissoides ; the third, which has 

 an oval head composed of several cells, in all species without 

 exception; the fourth, which has an oval head consisting of one 

 or more cells, in Momordica charantia, Liffa cylindrica, L. 

 acutangula, Citrullus vulgaris, Cucumis sativus (PL I. Fig. 8), 

 C. 3Ielo, Benincasa cerifera, Lagenaria vulgaris, Trichosantlies 

 cucumeroides, T. japonica, T. multiloha, and Cucurbita Pepo. 

 Among these the trichome of Benincasa cerifera is especially 

 characterized by having two processes at the apex (PL I. Fig. 

 9) ; that of Trichosantlies cucumeroides, by having a single 

 enlarged terminal cell (PL I. Fig. 10), and that of Cucurbtia 

 Pepo, by having the head consisting of two cells, one placed 

 above the other (PL I. Fig. 11). 



Cuticle. The cuticle on the stems is mostly thin and smooth. 

 As exceptions, however, are to be noted Actinostemma racemosum and 

 Gymnostemma cissoides, the former of which has the cuticle striated 

 at the angled portions, while the latter has it so on all surfaces. 



Collenchyma. The collenchyma is developed at the angles 



