ii6 COROLLIFLORsE, LONICERA. [CHAP. 



insects, but often fertilises itself, as the stamens 

 and pistil ripen simultaneously, Viburnum (the 

 Guelder Rose) secretes honey, and the flowers are 

 collected into a head as in the Elder, but the outer 

 florets have the corolla considerably enlarged at the 

 expense of the stamens and pistil. Although, there- 

 fore, they produce neither pollen nor seeds, they are 

 useful to the plant, by rendering the other flowers 

 more conspicuous, and thus attracting insects. In 

 remarkable contrast to these species, with their ex- 

 posed honey, is the genus Lonicera (the honeysuckle). 

 Lonicera caprifolium has a honey tube no less than 

 30 mm. long, for the most part not above I 2 mm. 

 wide, and moreover a great part occupied by the style. 

 It is often, however, half full of honey. As in the 

 longest tongued bees (Bombus hortonnn and AntJw- 

 pliora pilipes), the proboscis only attains a length of 

 21 mm., those of Flies (Rkingia, Bombylius discolor} 

 not more than H--I2 mm., they are none of them 

 in a position to extract all the honey ; and in fact 

 Muller never found them attempting to do so, though 

 they visit the flowers for the pollen. The honey 

 of Lonicera caprifolium is therefore especially adapted 

 for the larger moths. The flowers open in the even- 

 ing, and are then specially fragrant. Muller found 

 the following moths on this species : Sphinx convol- 

 vuli ; S. ligustri ; S.pinastri; Deilephila elpenor ; D. 

 porcellus ; Smerinthus tilics ; DiantJuzcia capsincola, 

 Cucullia uvibratica, Plusia gamma, Dasyclura pudi- 

 bunda. 



L. periclymemnn (the Common Honeysuckle) 

 agrees in most respects with the preceding species, 



