FLOWER-GROUPS 63 



5. Form with immobile flowers {lypus immoiiflorus) : Sparganium, Typha, 

 Potamogeton, Triglochin, many Palms. 



III. Zoidiophilae (^Animal-pollinated Plants): after correspondence with 

 Hermann Miiller, Delpino proposed to divide this group of floral arrange- 

 ments as follows (according to Herm. Miiller, 'Fertilisation,' pp. 15-16): — 



(a) Ornithophilae (^Bird-pollinated Plants) : plants with flowers pollinated by 

 the agency of honey-sucking birds, or those that capture small insects 

 (Trochilus, Nectarinia, and others). Many of these flowers are exceedingly 

 large and saccular. They are characterized by their vertical position 

 and brilliant (especially scarlet) colours, and they often secrete large 

 quantities of nectar. 



{i) Malacophilae (Snail-pollinated and Slug-pollinated Plants) : plants with 

 flowers polhnated by the agency of snails or slugs. The flowers are 

 so closely crowded that in gliding over them these creatures must come 

 into contact with pollen and stigmas. Some of these are protected 

 against the injurious effects of their voracious visitors by secreting an 

 irritant fluid that is fatal to snails and slugs (Alocasia odora), or by con- 

 version of their perianth into a fleshy, edible tissue, with the consumption 

 of which the visitors are satisfied (Rhodea japonica). 



{c) Entomophilae (Insect-pollinated Plants) : plants with flowers pollinated by 

 the agency of insects. To this group belong all the plants indigenous 

 to Europe that are popularly known as ' flowers,' i. e. flowers that are 

 immediately conspicuous to us, and to their visitors, through their bright 

 colour, pleasant odour, or both (Herm. Miiller, 'Fertilisation,' p. 16, 

 note). Delpino distinguishes the following special sub-groups : — 



1 . Melittophilae (with Large-Bee Flowers) : plants with flowers pollinated by the 

 agency of large bees. These are day-flowers, of which the colours and odours are 

 also agreeable to man ; some of them possess concealed nectar (Salvia pratensis). 

 Others are devoid of nectar, and these possess hidden pollen, which only appears 

 after special treatment (Genista tinctoria*) '. 



2. Micromellittophilae (with Small-Bee Flowers) : plants with flowers pollinated by 

 small bees (and a great variety of other small insects). They influence the visitors to 

 a much higher degree than in the case of any other plants (Herminium Monorchis ? *). 



3. Myiophilae {with Fly Flowers) : plants with flowers pollinated by Dipterids 

 of all kinds. The flowers are mostly dull in colour (yellowish, claret, spotted), 

 and usually have a smell that is disagreeable both to men and to bees. The nectar 

 is quite exposed, or there is pollen only (Euonymus). 



4. Micromyiophilae (with Small-Fly Flowers) : plants with flowers pollinated by 

 tiny Dipterids. The flower or the inflorescence forms a closed chamber with narrow 

 entrance, and this serves often as a temporary prison for the visitors. There is 

 an extremely thin layer of nectar, or none at all, but in the latter case there is 

 abundant pollen (Aristolochia Clematitis, Arum). 



5. Sapromyiophilae {with Carrion-Fly Flowers) : plants with flowers pollinated 



' Forms indicated by * have been added by Hermann Miiller, from his own lists, to Delpino's 

 groups. 



