82 THE POPULAR SCIENCE MONTHLY. 



even here, the calyx has extremely long, narrow teeth, thickly covered 

 with smooth hairs, which serve to keep its beans safe. The analogy 

 of a prickly pear or a rose-hip will show how very unpleasant such 

 hairs feel in the mouth. The beautiful, small barefoot clover derives 

 its expressive name from a further development of the same principle. 

 The long teeth of the calyx project beyond the flowers, and are envel- 

 oped in soft, downy hair, which gives the whole head a very dainty, 

 feathery appearance. As soon as the flowers are faded, the head looks 

 like a mere mass of soft fluff, unenticing to herbivorous animals, and 

 effectually concealing the seeds from birds or insects. The starry 

 clover of Southern Europe, naturalized in England at Shoreham and a 

 few other spots, starts from much the same point, but has specialized 

 itself both against large and small depredators. On the one hand, its 

 smooth, woolly calyx, much like that of crimson clover during the flow- 

 ering stage, spreads out after blossoming into a star-shaped pattern, 

 and forms with its neighbors a dry, bristly, interlacing head, thickly 

 studded with sharp hairs ; and this suffices to protect it from cattle 

 and goats. On the other hand, the mouth of the calyx, being thus 

 exposed by the spreading of the teeth, is closed by a perfect cheval- 

 de-frise of convergent tufted hairs, all meeting in the center of the 

 throat ; and this barrier answers the same purpose as that of the ser 

 clover, though in a different manner, by forming a false bottom to ex 

 elude insects. I notice on the dry Mediterranean hills that these bristlj 

 heads are rejected by the goats and sheep, like those of Boccone's clo- 

 ver, and even donkeys refuse to eat them. 



Turning to a somewhat different class, there are some clovers which 

 protect their seeds in a quite distinct manner, by merely turning them 

 out of sight. Common Dutch clover does this in a simple yet very 

 noticeable fashion. It bears its pretty white flowers in tall globular 

 heads on a lengthened footstalk, which renders them extremely con- 

 spicuous objects to the fertilizing bees. But each flower is stalked 

 within the head, and, as soon as it has been fertilized, it turns down- 

 ward, and fades brown against the common footstalk. Every head of 

 Dutch clover thus habitually consists of two parts — an upper part, 

 containing erect open flowers or flower-buds, not yet fertilized ; and a 

 lower part, containing overblown flowers, already fertilized, and now 

 engaged in setting their seed. This plan combines two distinct ad- 

 vantages at once. In the first place, the bees lose no time in discrimi- 

 nating between the mature honey-bearing blossoms and those already 

 rifled, which insures more frequent visits and a larger general average 

 of seed-setting. In the second place, the fruiting pedicels and pods, 

 being turned down and concealed, are less likely to be visited by small 

 animal foes, such as flying insects, which might lay their eggs within, 

 and let the grub feed (as often happens) on the growing seed. Dutch 

 clover is a fodder-plant, and therefore, probably, in its native state 

 does not grow much in places exposed to the ravages of large herbi- 



