1 8 Wi/son — Observations on 



size of its cells and of the intercellular spaces, the parenchyma 

 of the leaf stalk. In some of the cells are leucoplasts, but 

 they are erratically distributed and not numerous. The clear 

 refractive bodies, probably a glucoside, mentioned as existing 

 in the cells of the young flowering shoots, but absent from 

 the adult stalk, are here very abundant. 



The bundles are collateral, as in the flowering shoot, lie 

 parallel to each other, and vary in number from seven to 

 eleven. Usually three of them are larger than the others. 



X. Flowers. 



The description of the flower has been already given, and 

 allusion made to a rudimentary ovarian gland seen in a cross 

 section of a young flower bud. This ovarian gland is particu- 

 larly interesting in view of the fact that a well developed one 

 is found in the adult flowers of Phclipa;a, which in this and 

 many other respects, already noted, closely correspond with 

 those of Conopholis. 



The fruit of C. americana is a two-valved, single-celled 

 capsule. On the middle of each valve are developed two 

 parietal placentae bearing numerous seeds of fair size. 



The seeds have well-developed endosperm, with small 

 undifferentiated embryos. 



A detailed study of the floral structure and of the embryo- 

 logy will be given in a later paper. 



The following is a brief summar)'' of results : 



1. Co7iopholis is parasitic on the oak, and may form a fringe 

 of growth round the trunk, at a distance of ten or more feet. 



2. It is perennial to the extent of at least eight to ten years. 



3. It first affects young roots, and usually starves the portion 

 beyond the point of infection. 



4. The union between parasite and host is an extremely 

 intimate one, the parasite being practically developed endo- 

 genously within its host, which rises up and encloses it after its 



