HISTORICAL DEVELOPMENT OF FLOWER POLLINATION 23 
Eggers, Henslow, Meehan, Coulter, Bush, Battandier, Errera and Gevaert; on 
self-sterility by Gentry, Warming, Meehan, Delpino, Ludwig, Schneck, Rimpau, 
Liebenberg, Hoffmann, Neubert, Focke, Eggers, Hunger, Battandier; on self-fertility 
by Pedicino, Comes, Meehan, Caruel, Wilson, Henslow, Asa Gray, Delpino, Ludwig, 
Hoffmann; on the relations between crossing and self-fertilization by Henslow, 
Meehan, Pedicino, Caruel, Comes. Cultivation and pollination researches were 
carried out by Hoffmann, Wilson, Rimpau, Liebenberg, Beal, Vilmorin, Ottavi, 
Horvath. 
Within a few years after the appearance of the first of Miiller’s works, Errera 
and Gevaert were able to publish a summary of the various arrangements for 
pollination known up to 1878, in their work ‘Sur la structure et les modes de 
fécondation des fleurs’ (Bul. Soc. roy. bot., Gand, xvii, 1878). Loew (‘Ein- 
fiihrung,’ pp. 324-7) gives this summary as follows :— 
I. MONOMORPHOUS INDIVIDUALS, i.e. in respect of flowers all the indi- 
viduals are alike. 
1. Monomorruous Frowers. All flowers alike, and hermaphrodite. 
A. Cleistogamy (Kuhn), All the flowers remain permanently closed; 
crossing is impossible. 
B. Chasmogamy (Axell). All flowers open; crossing is always possible. 
(2) Direct Autogamy. The pollen falls directly on the stigma of the same 
flower. 
a, Direct Autocarpy. Self-pollination is effective: Trifolium arvense. 
B. Vo direct Autocarpy. Self-pollination is not effective: Corydalis cava. 
(4) No direct Autogamy. The pollen does not fall directly on the stigma. 
a, Herkogamy (Axell). The mature anthers and stigmas are remote from 
one another: Anacamptis pyramidalis. 
8. Dichogamy (Sprengel). The anthers and stigmas are mature at different 
times. 
* Proterandry (Delpino). The anthers open before the stigmas are ready 
for pollination: Teucrium Scorodonia. 
** Proterogyny (Delpino). The stigmas are ready for pollination before 
the opening of the anthers: Aristolochia Clematitis. 
2. PreomorrHous Frowers. The flowers of various individuals are different. 
A. Chasmo-Cleistogamy (Delpino). The constantly hermaphrodite flowers 
differ from one another in the mode of pollination, some being cleistogamous, others 
chasmogamous: Oxalis Acetosella. 
B. Monoecism. The flowers of the same stock differ from one another in 
sex: there are always a few flowers that are not hermaphrodite. 
(2) Dimonoecism. The flowers of the same individual are of two kinds. 
a. Andromonoecism (Darwin). Flowers hermaphrodite and male: Veratrum 
album. 
B. Gynomonoecism (Darwin). Flowers hermaphrodite and female: Parietaria 
officinalis. 
