Of Aphyllon Uniflorum, Gray. 1 1 7 



bundle-strands enter each lobe singl}-, but immediately divide 

 into three main branches. 



The upper lip of the tubular corolla consists of two some- 

 what recur\'ed lobes, the lower of three lobes. Each lobe is 

 supported by two main strands of bundle-tissue, which enter 

 separately as branches of the bundle-ring in the floor of the 

 flower. The outer surface of the corolla bears many hairs 

 above the line where the calyx lies against it, the inner surface 

 not nearly so many. These hairs arc all of the same type, 

 having a stalk of several cells placed end to end, and a round 

 head formed of (usually) eight radially arranged cells. The 

 four epipetalous stamens are didynamous, the posterior pair 

 being the shorter. The anther-lobes are formed in the usual 

 way, having at first four and later two loculi. The micro- 

 spores are small and spherical. 



The unilocular ovary consists of antero-posterior carpels. 

 Externally it is quadrangular in shape, corresponding to the 

 positions of the four placentas, and the style bends forward 

 so that the broad bilobed stigma lies at the anterior part 

 of the mouth of the flower-tube. At the base of the ante- 

 rior carpel is a large nectary sunk into the tissues of the 

 carpel (Plate XV, Fig. 7). In cross section the ovary shows 

 an epidermal layer of high columnar cells, the outer walls of 

 which are thickened. Within are several (four or five) layers 

 of rounded cells. The four parietal placentas are cushion-like 

 ingrowths of similar rounded cells, the entire ovarian wall being 

 packed with starch. A well-marked bundle-strand is present 

 in the middle of each carpel, the position of the bundle being 

 indicated externally by anterior and posterior grooves on the 

 surface of the ovar>^ The small anatropous ovules are pro- 

 duced in great numbers (Plate XIV, Fig. 4). 



The nectary shows in cross section seven to nine layers of 

 gland cells, which are readily distinguishable by their small 

 size, rounded outline, the absence of starch, their granular. 



