3 2 FLOWERS OF THE FIELDS AND MEADOWS 



these are the two wings or alse. The other two lower petals are 

 united along the anterior margin to form a carina or keel. 



The nine stamens are united at the base to form a tube encircling 

 the pistil, and project beyond it into a triangular cavity at the bottom 

 of the keel which is a repository for pollen. The tenth is free. The 

 alae are locked by projecting knobs fitting into a hollow opposite (as 

 in the mantle of a Sepia or Cuttle-fish). An insect alighting on the 

 flower bears down the alae and the keel, which is pushed over the 

 column or ring of stamens and forces the pollen up into the cavity 

 and against the abdomen of the insect, and when the insect goes off 

 to another flower the parts return again to their former position and 

 cover up the pollen. The bee is able to reach the honey when the 

 tenth stamen is free. In other species of Leguminosae where the tenth 

 stamen is united there is usually no honey. 



Pollen is discharged when the anthers burst before the flowers are 

 opened. Of the two groups of five stamens one has thickened ends, 

 and after the five inner anthers have shrivelled they fill the hollow in 

 the keel in which the pollen is collected. The wings and keel are 

 both depressed when a bee alights, and being locked together they 

 spring back as by a "piston mechanism" after pressure is removed. 



The visitors are Hymenoptera (Apidse), Diptera, Sphinges, Sesia, 

 Zygccna, Bombyces, Porthesia, Noctuce, Euclidia, &c. 



The pod is a many-seeded fruit, and is divided into divisions which 

 alternate with the seeds, and as the chambers break off when the pod 

 is ripe, the seeds travel to a short distance, and the Bird's Foot Trefoil 

 is therefore extended in range by its own agency. 



This plant is best suited by a sand soil in which there is a fair 

 proportion of clay, or sandy loam, and is therefore both a sand-lover 

 and a clay-lover. It is abundant on Triassic and Liassic clays as 

 well as on later Oolitic rock soils. 



The fungi Peronospora trifoliorum and Uromyces striatus attack 

 Lotus. The beetles Apion loti, Bruchus loti, Meligethes solidus, a 

 hymenopterous insect Megackile argentata, and the Lepidoptera, 

 Dusky Skipper, Wood W T hite, Common Blue, Clifden Blue, Common 

 Heath, Gelechia tumidclla, G. tceniolella, Nepticula cryptella, Silver 

 Cloud (Xylomyges conspicillaris}, &c., Transparent Burnet (Zygcena 

 minos], Broad-bordered Five-spotted Burnet (Z. trifolii], Narrow- 

 bordered Five-spotted Burnet (Z. lonicera), Litlwsia palliate lla, 

 Coleophora discordella, Bordered Gray (Selidosema plumaria), and 

 Myllophila semi-rubella, and the fly Diplosis loti feed on it. 



Lotus, a name given by Theophrastus, is the Latin for this common 



