Briefe. 
107 
a week or so after the expansion of the flowers, the entrance of the stigmatic 
cavity being open. 
As to Notylia I may add that nectar is secreted at the base of the bracteae 
and also at the base of the upper sepalon. 1 found nectar at the base of the 
bracteae in a small species of Oncidium also 
At last I have gratified my wish of examining myself the wonderful genus 
Catasetum (Fig. 33). I had three fine racemes of the male Catasetum mentosum and 
•^^g- 33- Catasetum mentosum (J, 5. December 1866. i von der Seite. 2 halb von unten. 3 Lippe 
von unten, 4 von der Seite. 5 Längsschnitt der Lippe. 6 Säule von vorne; von der Seite, a -Staub- 
beutel, p Füsschen, d Klebscheibe, s Narbenkammer, m Haut, welche die beiden Fühlhörner verbindet. 
7 Pollinien. Aus dem Nachlass. 
one raceme with only three flowers of Monachanthus (probably of the same species). 
In this Catasetum a membrane connects the antennae with the interior margin of 
the stigmatic Chamber. The ovula are scarcely more rudimentary than in 
Monachanthus, and not so much so, as in many other Vandeae, The stigmatic 
surface is not viscid at all; but notwithstanding pollen-masses (from the same as 
well as from a distinct plant and also from Cattleya Leopoldi), when introduced, 
began to dissolve into groups of pollen grains and to emit tubes, some of which 
wäre 2 long, . . . the flowers withered. — 
l) Vgl. Darwin, Fertilization of Orchids, 2d edition, 1877, p. 266. Herausgeber. 
