632 Staber: The anatomy of Sesban macrocarpa 



sunken owing to the papillose character of the epidermal cells. 

 The neighboring cells, three or more, were arranged in no partic- 

 iilar order. Epidermal hairs and glandular cells were lacking, the 

 latter often being found among the Galegeae. The leaf-bundles 

 had no sclerenchyma sheath, but lay embedded in the mesophyl. 

 A few crystals of calcium oxalate w^ere found in the bundles. The 

 palisade parenchyma of two layers was rich in chlorophyl ; some 

 of the cells, however, were full of tannin. The spongy paren- 

 chyma, below, was two-layered, many cells of which also contained 



tannin. 



The seeds of this plant were invested by an unusually hard 

 resistant seed coat, which refused to split after the usual soaking, 

 except for a very small percentage. Heroic measures were then 

 resorted to. The seeds were put into boiling water and boiled for 

 a minute or a trifle more. After this treatment every one sprouted. 

 Very little anatomical work has been done upon this genus. 

 The tannin-ducts have been examined by Trecul, the leaf by 

 Weyland, and the floating roots by Schenck and by Scott and 

 Wagner, all of which have been referred to in the preceding pages. 

 In summing up, therefore, we find in Sesban macrocarpa the 

 commonly recognized anatomical characters of the Leguminosae, 

 except that some of the ducts in the roots have fan-like cross- 

 walls in place of simple openings. As for the further characteris- 

 tics of the Papilionaceae, we find that Sesban macrocarpa has the 

 tannin-ducts, but wholly lacks hairs of any kind. As for the cal- 

 cium oxalate secretion, it was found only in the leaf-bundles. Of 

 special interest maybe mentioned the lateral and twin sieve-plates, 

 lateral openings in the annular ducts, the bast or stereome and the 

 libriform fibers having the third membrane, and the resistant coat 

 of the seeds, besides the disappearance of the endodermis in the 

 old stem. 



■ 



The study of Sesban macrocarpa was carried on in the Barnard 

 Botanical Laboratory, under the direction of Professor Herbert M.. 

 Richards, to whom his student gratefully acknowledges her appre- 

 ciation of his help and interest. The original material and seeds 

 were kindly supplied by Dr. D. T. MacDougal of the Carnegie 

 Institution of Washington, to whom the writer wishes to express 

 her thanks. Thanks are due also to Miss Alice A. Knox for her 



