78 FARMERS' INSTITUTES. 



filiform, stigmas oblique or dorsal ; ovules few. Pod small, in dehiscent, 1-4 

 seeded, nearly enclosed in the calyx. Found in the north, temperate and 

 warm regions, rare in southern ; species, 150. 



T. PRATENSE, L. RED CLOVER. BROAD LEAVED CLOVER. COMMON 



CLOVER. MEADOW TREFOIL. 



More or less pubescent, leaflets oblong, stipules membranous, free portion 

 oppressed to the petiole, heads terminal, sessile globose, at length ovoid, sub- 

 tended by opposite leaves with much dilated stipules, calyx-teeth slender 

 setaceous, erect or spreading in fruit, the lowest longest. 



Pastures, roadsides, etc., both wild and cultivated; ascending to 1,900 

 feet in the Highlands [of Great Britain] ; flowers from May to September. 

 Annual, biennial, or perennial. Stems G — 24 inches, solid or fistular, 

 robust or slender. Leaflets i, — 2 inches, often marked with a white spot or 

 hmal band, finely toothed; stipules often 1 — 1-|- inches, with long setaceous 

 points. Heads \ — li inches diameter, pink, purple, or dirty white. Cahjx- 

 tuhe with a two-lipped contraction in the throat, strongly nerved; teeth not 

 exceeding the petals, very slender, unequal. Pod opening by the top falling 

 off. Found in Europe, North Africa, Siberia, Western Asia to India; 

 ■introduced in North America certainly before the Kevolution. 



Red clover usually has a large tap root with numerous branches extending 

 in all directions. Sometimes the tap root is short, and soon equalled by its 

 branches. The roots rarely ever extend less than two feet below the surface, 

 as in moist compost land, or where the surface is very rich. Where the 

 subsoil is at all open and inclined to be dry it is not unusual for the roots of 

 clover to reach down six feet or more below the surface; however, the main 

 bulk of the roots are usually within a foot of the surface. Various experi- 

 ments" and careful estimates have shown that fully one half the weight of a 

 clover plant is below ground in the form of roots. 



Concerning the stems and leaves I shall speak more in detail in the para- 

 graph which treats of variation of the plant. 



The flower is irregular, papilianaceous, and its structure rather difficult to 

 understand without considerable study of specimens or good illustrations. 



The nectar is secreted by small glands at the base, on the inside of the tube 

 formed by the cohesion of the nine inferior filaments, and accumulates 

 around the base of the ovary. In the center of the flower is the pistil, the 

 style of which curves upwards, carrying the stigma a little beyond the anthers. 

 The tenth stamen is free and for most of its length is turned to one side, 

 making it quite easy for the long tongue of a bee to reach the nectar. 



In the words of Miihler, "^If now a bee inserts its proboscis beneath the 

 vexillum, while it clings with its forelegs on to the alse (which are coherent 

 with the carina), resting its middle and hind legs on a lower part of the 

 inflorescence, the carina and alse are drawn downwards, and the stigmas .and 

 anthers are thrust up against the under side of the bee's head ; the stigma, 

 standing highest, receives the pollen brought by the bee, and instantly after- 

 wards the anthers dust the bee with fresh pollen. Cross -fertilization is thus 

 insured ; self-fertilization may take place as the bee draws back its head, but 

 is probably neutralized and superseded by the immediately preceding cross- 

 fertilization. In order to reach the honey in this way (to the bottom of the 

 tube) an insect must possess a proboscis at least nine to ten m. m. long. The 

 pollen is accessible to all insects which can press down the carina, and such 



