64 T. Holm — Erigenia bullosa. 



but an anatomical study of the specimens proved these to be 

 seedlings of Claytonia Yirginica, which germinates with a 

 single cotyledon. Bat those of Erigenia, which we found 

 last spring, did not only exhibit a single cotyledon, but they 

 showed besides all the anatomical details, the characteristic oil- 

 ducts for instance, as were familiar to us from the study of 

 full-grown individuals ; moreover these little seedlings showed 

 a minute tuberous body at the base of the cotyledon. 



Erigenia bullosa seems to be rare in the vicinity of Wash- 

 ington, D. C, and has so far only been recorded from High 

 Island and Plummer's Island ; it is also found on the muddy 

 river shore at Great Falls, Maryland, where we discovered it a 

 few years ago. It prefers low, shaded grounds, and was found 

 associated with such plants as Dicentra, Trillium, Caulophyl- 

 lum, Jeffersonia and Erythronium. It may be found in 

 bloom as early as the month of March or the beginning of 

 April, and the seedlings appear at the same time. It is by no 

 means acaulescent, but the stem is very low and bears a few 

 stem-leaves and umbels, which are held in an erect position 

 during anthesis. In the fruiting stage the stems bend down 

 towards the ground, though without buying the fruits. 

 These are said to fall off before maturity, a statement we can- 

 not confirm, at least not according to our own observations. 

 The seedlings are small, but occur in large numbers with the 

 older plants, and the color of the cotyledonar leaf-blade is of 

 the same deep green as the leaves of mature specimens. The 

 blade of the cotyledon is held in a horizontal position, raised 

 above the ground by a long, slender petiole (fig, 1). As 

 already stated, a small light brown, tuberous body is to be 

 noticed at the base of the cotyledon and this is the first indica- 

 tion of the globular root, which represents one of the charac- 

 ters of the genus, the monotypical Erigenia. 



The tuber is at this stage about 2 mm in length, and tapers 

 almost gradually into a filiform, unbranched root, covered by 

 root-hairs, which are not very numerous, however. We 

 observed, on the other hand, no root-hairs on the tuber itself 

 and suspected, thus, that it represented the hypocotyl, but by 

 examining its internal structure we felt convinced that it 

 actually represents the basal portion of the primary root itself ; 

 the filiform part of the root does not grow out any further, 

 but dies off during the first season. No other leaf than the 

 cotyledon develops in the first year, and the plumule stays 

 underground concealed in the sheathing base of the cotyledon. 

 In the month of May the cotyledon had already faded away 

 entirely, and the same was, also, the case with the leaves and 

 stems of older specimens. In the second year after germina- 

 tion has taken place, the first proper leaf pushes up through 



