tf&S THE LOWER DICOTYLEDONS. 



Note the following interesting features in the vegetative 

 organs : the runners of Strawberry and of some Potentillas ; 

 the suckers of Easpberry ; the long shoots of some Brambles 

 which grow into the soil at the tips, producing roots which 

 contract and pull the tip down, and the formation of new 

 plants in this way ; the prickles of Eoses, Brambles, Easp- 

 berry ; the spines of Sloe and Hawthorn ; the curious glands 

 on the petiole of Cherry, just below the leaf -blade ; the ever- 

 green leaves of the introduced bat commonly cultivated 

 Cherry Laurel and Portugal Laurel, both belonging to the 

 Cherry genus (Prunus). 



342. Flower Mechanisms in Bosaceae. In most 

 Eosaceae the flowers, which are regular and show all degrees 

 of perigyny, are insect-pollinated (except Salad Burnet) and 



RECEPTACLE 

 Pig. 184. Longitudinal Section of Flower of Blackberry (Bramble). 



mostly visited by all sorts of insects. In most cases honey 

 is produced by the whole inner surface of the receptacle, or 

 there is a ring-like nectary (disc, Fig. 134) round the re- 

 ceptacle mouth within the insertion of the stamens ; Dog 

 Eose, Agrimony, Meadowsweet, and Dropwort are honeyless 

 pollen-flowers. Lady's Mantle and the smaller Potentillas 

 are visited by flies, Cotoneaster chiefly by wasps. 



In Prunus (Cherry, etc.) and the larger-flowered Pyrus- 

 types (Apple, etc.) the stamens form a sort of palisade, which 



