PART III. | THE MECHANTSMS OF FLOWERS. 565 
Peyritsch, from Central Africa, remain with their inflorescence, 
which consists of male and female flowers, and is inclosed within 
a spathe (like our Arwm), beneath the ground; the tip only pro- 
trudes, and by it the fertilismg agents creep into the floral 
chamber. A similar condition exists in Liarwm and Cryptocoryne 
(222). 
Calla palustris, L—This plant exhibits a first step towards 
the condition of things which is perfected in Arum maculatum. 
Its disgusting smell protects it from injurious animals, and attracts 
carrion-loving flies. The white spathe is very conspicuous, and the 
proterogynous condition is very distinctly marked (590, 1.). . Eug. 
Warming (762) attributes a share in the work of fertilisation to 
pond-snails, 
Symplocarpus fatidus—This shows an intermediate stage 
between the open spathe of Calla palustris and the closed 
prison of Arwm maculatum (728). 
In Ambrosinia Bassii the anthers are within the spathe, the 
stigmas outside, at the end of the spadix. The fertilising agents 
(flies) creep down the spadix, and so in each plant come in contact 
with the stigmas before the anthers (178, p. 230). 
Anthurium Pothos is proterogynous with short-lived stigmas, 
like most other Aroidez (177, p. 62). 
Orv. LEMNACEZ. 
Lemna minor, L., according to Ludwig, is adapted for fertilisation 
by insects which live upon the surface of the water; so also, 
apparently, are L. trisulea, L. gibba, and L. polyrrhiza (435). 
Orv. ALISMAC EZ. 
398. AtismA PLANTAGO, L.—The three white or reddish petals 
are yellow at the base, and expand to form a disk about 10 mm. 
in diameter. 
The chief visitors are Syrphidz. They alight sometimes in 
the middle of a flower, in which case the insect’s belly comes in 
contact with the stigmas and immediately afterwards with the 
anthers; or they alight on one of the petals and creep towards the 
pollen or honey, in which case various parts of the insect’s body 
come in contact with the anthers, and sometimes also with the 
stigmas. 
