114 ERIOCAULONE. 
dentatis, striatis, parce albo-barbatis. Corollis ciliatis, apicibus 
barbula alba minima maculaque nigrescente, calyce simplici. 
9, 4, Uncialis, glaucescens. 
Habit Paludib Mergue : August,. 1834. 
Rhizomate annuo, fol. angusti-lanceolatis basibus arachnoi- 
deis: vaginis longioribus, scapis, 3-4 pollicarib, vaginis folia- 
que superantib., capitulis hzemisphericis cinereis, involucris 
squamis nudis bracteolisquf spathutatis, denticulatis, bracteo- 
lis ad apices parce albo-barbatulis, calycibus nudis : corollis fze- 
min. ciliatis, cum masculis apicibus barba minima alba macu- 
laque nigrescente. Mergue herb. No. 254. 
On the Anatomy of Ériocaulonec. 
The axis in most species exists in the shape of Rhizomata: 
in one instance, (E. setaceum) the only instance with which 
I am acquainted, it is really caulescent, and occasionally 
branched. In this species it consists of a central vascular 
part, the space between this and the cuticle being occupied 
by a vast quantity of irregular air cells. By air cells, I 
mean those cavities which apparently contain air, and the pa- 
rietes of which are built up of cellular tissue. 'The Rhizomata 
offer nothing worthy of notice. The roots are in general, 
simple. 
With respect to the structure and distribution of vessels, 
they appear without exception to be destitute of spiral vessels ; 
a curious fact, since they rank tolerably high in the scale of ye- 
getation. The place of these is supplied by ducts, which occur 
aggregated in distinct fascicles, and surrounded by cellular tis- 
sue of a moreor less elongated form. "They are occasionally, 
but not freely unrollable, and = have been at ап early 
period spiral vessels. 
-Itis well known that many planes: are furnished in their 
latest developed part with spiral vessels, while ducts only 
are found in the older parts. This is particularly the case 
