1909] 



BARBER-FRUITS AND SEEDS OF CUCURBIT 'ACEAE 



283 



CUCUMIS SATIVUS L. 



Cucumis sativus L. (cucumber) occurs native in the East Indies, 

 and from this species have been derived many varieties which have 



long been cultivated in gardens. 



The fruit varies in size, but is always elongated or oval, and rounded 

 triangular in cross-section. It is fleshy and solid, without a central 

 cavity, and of a yellow-white color with white fruit-flesh. Numer u> 

 wans cover the surface, each capped with a short 

 blunt spine which readily becomes detached dur- 

 ing growth or on handling. 



the three locules, 



(fig 



are 1 



seldom 



T P-cm 



in length, flattened. 



sativu s 



3. — Cucumis 

 L. Seed. 



over 2 mm thick, and are not, like those of X i. 



Cucurbita, provided with a border. 



(figs 



This consists only of the solid fruit-flesh, 



the bundles occurring throughout the mesocarp and not mac 



entral 



cavity. 



in 



i- Epicarp (epi)— The prismatic cells form a palisade layer 7 5 /* 

 width, with strongly thickened outer and radial walls, and very 



thin inner ones. The intense color 

 of the fruit is due, not to the cell 

 contents, but to the yellow walls. 



The warts, which appear before 

 fertilization of the flower, have the 



cell structure as the outer 



same 



^ 



large cells w 



pericarp. Each bears 

 -J (fig- TI ) consisting of 

 ,-ith thickened, sparingly 



pitted walls. They grow rapidly for 

 a short time, but lose their contcnt- 



h 



10 



soon after their w 

 thicken. 



alls 



begin 



"*<ure enif "'" S<UivUS U Im ' 

 fcndnl, I P ln cros s-section, with 



Cncuti! ^ X 160. -Fig. 10. 



* cZ\l allVUs L Immature seed 



tver , tl0n: Car > j nner carpellary 



Whair* outer integument; In', 

 "* tegument. X200. 



At its apex the emergence bears 



inted (up to ten cells), 



a long, joi 



conical hair, with thickened walls. 

 The cross walls and inner sunken 

 foot, also thickened, arc pitted (/). 



