280 PROCEEDINGS OF THE ACADEMY OF [1888. 



plant seem different. Tlie flowers in all three turn yellow soon after 

 they open. 



On account of this change, the plant is known as "Silver and 

 Gold " in Japan. 



The floAvers open towards evening. At the expansion of the co- 

 rolla, the stamens and pistil are of equal length. The flower is pro- 

 terogyuous. In the morning the stigmas Avill adhere, if brought 

 together l)y their viscid secretions; but the anthers do not disperse 

 pollen till later. The expanded flower remains white or I'osy-tinted 

 all the day after opening, and turns yellow the second day, fading 

 the third. The tube of the corolla is about an inch long. On the 

 evening of expansion it contains no honeyed secretion. In the 

 morning the production of nectar is coeval with the bursting of the 

 anther cells, by noon the sweet liquid has risen up the tube for about 

 one-third its length. It continues to flow after the change to yellow; 

 and by evening, the tube is full for half its length, or half an inch. 

 When the flower Avholly fades, the sweet secretion, which gives the 

 name of honeysuckle to the family is still there. Amid all these points 

 of uniformity", there are differences in productiveness. The form 

 known as L. braehybotrya is abundantly fertile ; in occasional in- 

 stances only do the others bear fruit. This is worth noting. Plants 

 twining on trellises, under exactly the same conditions, vary re- 

 markably in their reproductive powers. Such observations have 

 been made before on other plants, and are the facts regarded as puz- 

 zling. Mr. Darwin savs : — " Thev make me believe that some indi- 

 viduals of a species differ from others in their sexual afKnities (to 

 use the term employed by (raertner) like closely allied species of 

 the same genus." (Cross and Self-fertilizatiov, Chap, vi, p. 209.) 



As the expression "sexual affinity" does not explain anything, 

 and as these three honeysuckles are such very distinct individuals 

 as to have been regarded as distinct species of the same genus, they 

 suggested themselves as offering excellent o])portunities for observa- 

 tion as to the influence of anything that could be ufiderstood as being 

 in the nature of environment that might account for the origin of their 

 several forms; and especially what pai-t the visiis of insects might have 

 had in developing the general form of the whole flower. In the hon- 

 eysuckle, the tube of the flower attracts prominent attention. The 

 large amount of nectar it contains, gives the name of honeysuckle to 

 the family as already noted, and one cannot help referring to the ac- 

 cepted explanation of the origin of tubular forms. "]t may be 



