270 BRITISH FLOWERING PLANTS chap. 



bees. The leaves are glabrous above ; the under side is 

 covered by a waxy secretion, which protects the stomata 

 from being clogged by rain or dew. 



H. Miiller gives the following list of insect visitors 

 ■ — -twelve in number : — Coleoptera : Omalium Jlorale, 

 numerous, creeping about in the flowers. Diptera : 

 Bombylius discolor, numerous ; B. major, rarer, and 

 probably not often getting to the honey. Hymen- 

 optera : Bees : Anthrena gwynana, female, frequent on 

 the short-styled flowers ; Anthophora pilipes, both male 

 and female, very numerous ; the hive bee, sucking busily ; 

 Bomhus confusus, female ; B. hortorum, female, very 

 numerous ; B. lapidarius, female ; B. silvarum, female ; 

 B. terrestris, robbing the flower of its honey after biting 

 through the corolla ; Osmia rufa, male. 



HOTTONIA 



This genus resembles Primula in the position of 

 the honey, and in being dimorphous. It is sometimes 

 cleistogamous. 



H. palustris (Water Violet). — As in so many other 

 water plants the leaves are cut up into numerous narrow 

 linear lobes. That the plant was originally terrestrial is 

 indicated by the aerial flowers. The observations made 

 by Darwin on Primula were repeated and confirmed as 

 regards Hottonia by John Scott and subsequently by 

 H. Miiller. 



Cyclamen 



0. europssum. — The flowers produce no honey, but it 

 is supposed that insects pierce the delicate tissues inside 

 the flower and thus obtain a sweet sap. The flowers 

 are pendent, and being smooth and slippery, Kerner 

 has suggested that creeping insects are unable to get 

 round the lip, but slip off and fall down. The flowers 

 are protandrous, and the pollen is at first sticky, but 

 gradually becomes dry and pulverulent. The anthers 

 open at the apex. When the flowers first open, the 

 flower-stalk is bent nearly at a right angle, so that as 



