33 8 Schively — Contributions to the Life History of 



When young, all are somewhat pubescent, but the purple, 

 and green aerial when mature, bear hairs upon the sutures 

 only; those elsewhere have disappeared. The winter- type 

 possesses these epidermal structures through life and also 

 when ripe. Both long unicellular hairs and the bladder 

 forms, previously described, occur here. 



The terrestrial form presents several peculiar charac- 

 teristics. The purple coloring is due as elsewhere in the 

 plant, to a liquid either in the epidermal cells or just below 

 them. Stomata are quite as numerous comparatively, as 

 upon the surface of the overground legumes, but they are 

 here placed upon the apex of a small papilla raised con- 

 spicuously above the surrounding epidermal cells, which 

 resemble in size and shape those of the other legumes 

 (Plate XXXIV., Fig. 4). Certainly three kinds of hair 

 occur ; one of these has a base suggestive of a glandular 

 function. The others are of the same character as those 

 seen upon the aerial legumes, but are much more numer- 

 ous. A fourth kind may be the shorter unicellular seen 

 in the drawing. (Figs. 2, 3.) 



But instead of these walls being firm and unresisting, 

 they are thin and delicate. No sclerenchymatous fibres 

 exist, but there is present the parenchyma corresponding 

 to mesophyll in texture, whose cells also contain chloro- 

 phyll. The seeds occupy all the space within the legume, 

 and the result of the tension is seen by the final thin cover- 

 ing, as increase in size of the seed takes place. 



Remembering the great contrast in legumes produced 

 upon the lower axillary runners, due apparently entirely 

 to the special environmental conditions under which they 

 were allowed to mature fruit, an experiment was undertaken. 

 Some of the winter aerial legumes (not located upon the 

 lower runners) were buried, after they had become quite long, 

 but were still flat, the seeds being small and green. At 

 intervals during the course of a month they were exam- 

 ined ; at the end of that time a remarkable transformation 

 had taken place — the counterpart of a terrestrial presented 



