SOLANACEAE 



151 



Fig. 280. Lyctum vulgare. Dun. (after Herm. 

 Muller). (i) Flower seen, directly from the front. 

 (2) Do., partly dissected from the side, a, nectar- 



insect-visits may bring about self- and cross-pollination with equal ease. Should 

 these fail autogamy is inevitable. 



Kerner has described short-styled flowers 

 in which subsequent growth of the corolla for 

 about ^ cm. brings the anthers into contact 

 with the stigma, so that autogamy takes place. 



I observed the following mechanism in 

 long-styled flowers, especially those from the 

 neighbourhood of Kiel. The style is at first 

 somewhat longer than the stamens, and almost 

 always bent downwards, while the stamens 

 are bent upwards, thus separating the mature cover ; s}, stigma 

 stigma and the pollen-covered anthers. Bees 



when visiting the flowers climb up the style and stamens to the opening of the 

 corolla-tube touching first the stigma and then the anthers, and thus effecting 

 cross-pollination. Later on, when the flowers are already beginning to lose their 

 violet colour, the style and filaments straighten out, while the latter elongate to 

 some extent. Stigma and anthers are thus brought into contact, so that automatic 

 self-pollination takes place. 



Visitors. Herm. Muller 

 observed the honey-bee and 2 

 humble-bees (Bombus agrorum 

 F. 5, and B. lapidarius Z. 5) in 

 Westphalia, and his son the 

 following in Thuringia. 



A. Diptera. Syrphidae : 



1. Syrphus balteatus Deg., po- 

 dvg. B. Hymenoptera. 



Apidae : 2 . Anthophora aestivalis 

 Pz. J skg., J skg. and po-cltg. ; 

 3. A. quadrimaculata Pz. j and 

 $ in large numbers, skg. ; 4. Apis 

 mellifica Z. 5, skg. ; 5. Bombus 

 agrorum F. 5, do.; 6. B. ra- 

 jellus K. 2 and 5 skg. and po- 

 cltg. ; 7. B. sylvarum Z. 5, skg.; 

 8. B. tristis Seidl. 5, do. ; 9. 

 Eucera longicornis Z. S do., 5 

 skg. and po-cltg. ; 10. Melecta 

 luctuosa Scop. t>, skg. 



Alfken and Leege (L.) give 

 the following list for Juist. 



A. Diptera. {a) Musa'dae: i. Nemoraea radicum F. (d) Syrphidae: 



2. Pipizella virens F. B. Hymenoptera. (a) Apidae : 3. Bombus distinguendus 

 Mvr. 5, po-cltg. and skg.; 4. B. hortorum Z. ; 5. B. lucorum Z. 5 and S; 

 6, B. muscorum F. 5 and 5; 7. B. terrester Z. 5 and $; 8. Podalirius vulpinus Pz. 

 % rare, {b) Chrysididae : 9. Cleptes nitidulus F. 5, rare. C. Lepidoptera. 

 Noctuidae: 10. Plusia chrysitis Z., once (L.). 



Fig. 281. Lycium vulgare, Dun. (photographed from nature ; 

 X 3). (i) Flower in the first stage (cross-pollination) : the fila- 

 ments with their dehisced anthers are directed upwards, and the 

 style with its mature stigma downwards. (2) Do., in the second 

 stage (self-pollination) : anthers and stigma are brought so near 

 together that automatic self-pollination is brought about by direct 

 contact, a, anthers ; c, corolla ; s, stigma. 



To bring the flowers into their natural position they must be 

 supposed rotated through 90 to the left. 



