1892.] The Tendrils of Passiflora caerulea. 209 
mm. in length. These three regions show some well marked 
differences in structure and outline. The whole organ shows 
a bilateral organization which is least apparent in the base 
and most pronounced in the portion having the greatest power 
of movement, a recognized correlation given by Dr. Otto 
Miler.” 
The basal portion is broadly oval in outline with just a trace 
of flattening on the lower side; the middle portion is oval 
with its lateral much greater than the transverse diameter, 
while the lower surface is distinctly flattened. The tip is 
nearly circular in outline, and bears at its extreme end the 
cup-shaped formation above mentioned. Along the convex 
upper and lateral sides of the tendril are several obscure 
angles which are mostly absent from the lower concave 
surface, 
The internal structure of these parts shows corresponding 
differences. The arrangement in the middle portion is as fol- 
ows: The epidermis consists of a layer of rectangular cells 
with the longest diameter parallel to the long axis of the ten- 
dril (figs. 1, 2, 3, @). Occasional stomata are found distrib- 
uted equally over both surfaces.” 
Beneath the epidermis is a layer of collenchyma with thick- 
€nings so disposed that that the tangential are much heavier 
than the radial walls (figs. | Rae eae 6). Scattered through 
this tissue are the color bodies mentioned above. At the ob- 
tuse angles of the tendril this layer is three cells in thickness, 
at other places it decreases to one. : 
internal to this is a layer of loosely arranged thin walled 
ee of varying size, containing in the outer rows 0 
oman abundance of chlorophyll and protoplasm (figs. 1, 2, 
ae 1 Be ner rows of cells bordering on the bast ~ 
Shick, caded with starch, constituting the starch layer 
Through the entire layer are occasional crystals of calcium 
The cells of this layer on the convex side are unl- 
“responding difference in thickness of the layer. The in- 
eee ond i igt sie kein Krummungsver- 
Mungen» "et Bie bilateral gebaut st awite othelligt sie an den GRE: 
it Prerren 7: ee 2 
¥ Ti balgy of eae o Gh Spundte be botanische Practicum, 
