1914] PFEIFFER~THISMIA AMERICANA 125 
The indications were that the underground parts had wintered 
over, although seed-germination may have occurred and been 
overlooked, since the flower is all that appears above ground. 
Earlier descriptions of the Burmanniaceae gave little attention 
to any but the gross features, which were in the main correctly 
interpreted. Until recently, the work in anatomy has been done 
largely by Jonow (25, 26) in A pleria setacea, Gymnosiphon refractus, 
G. trinitatis, and Dictyostegia orobanchioides. The saprophytic 
forms worked with have scaly rhizomes, from which the flower 
stalks arise directly, as in Thismia. The adventitious roots are 
reported as being simple, with corky endodermis and a single, 
greatly reduced vascular bundle of lignified, dotted vessels, arranged 
in two concentric rings about one central spirally thickened element. 
The rhizome is described as having a structure much like that of the 
root. The erect stem or floral axis is credited with having bundles 
showing distinct xylem and phloem in most forms. The excep- 
tions are A pteria and Gymnosiphon trinitatis, which have such small 
bundles that the differentiation is difficult to recognize, according 
to JoHow. Nevertheless, he reports all cells of the bundle as 
lignified. 
Recently Ernst and BERNARD (9~20) have added largely to the 
knowledge of the anatomy of different saprophytic forms. They 
have considered Thismia javanica J. J. Sm., T. clandestina Mig., 
T. Versteegii J. J. Sm., Burmannia candida Engl., B. Championii, 
Thw., and B. coelestis Don (B. javanica Bl.). In these forms, the 
vascular elements in the root are much reduced; in 7. javanica (10) 
the bast alternates with thin-walled parenchyma cells about a 
central woody area, which is separated from the former by paren- 
chyma cells. The xylem region is figured as consisting of as many 
#$ 13 vessels. The fungus occurs in these roots in a patchy 
arrangement, infecting one group of cortical cells and not another. 
In the uninfected cells starch is common. 
In T. clandestina and T. Versteegii (13), a similar situation as 
regards arrangement of vascular elements is found, but the xylem 
'S not so conspicuous in amount. In the former species, there is 
but one subepidermal layer of fungi, in the latter two, the outer 
of which is the coarser. 
