i62 ANGIOSPERMAEDICOTYLEDONES 



Warnstorf describes the pollen-grains as orange-yellow in colour, ellipsoidal, 

 densely tuberculate, 37-40 /x long and 25-7 fi broad. 



In this species (and V. Thapsus Z., V. phlomoides, Z., V. pulverulentum Vill^ 

 V, Lychnitis Z., V. Blattaria L., and V. blattarioides ? auc/.), according to Maury, tl 

 anthers dehisce and touch the stigma when the flowers open. This does not 

 however, result in fertilization, for the stigmatic papillae are not yet developed, 

 this time, too, the conducting tissue of the style is very dense, offering gre 

 resistance to the penetration of pollen-tubes, and the ovules are immature 

 Pollination becomes effective later on, when it is effected by insect visitors, 

 as the result of contact between the pollen-covered anthers and stigma resultii 

 from the fall of the corolla, 



Schulz observed gynomonoecism, rarely gynodioecism. 



Visitors. The following were recorded by the observers, and for the localities 

 stated. 



Herm. Miiller (Alps), 3 Muscids, a Syrphid, 3 humble-bees, a true wasp, and 

 a Lepidopterid. Knuth (on garden plants), 2 po-cltg. humble-bees (Bom bus 

 agrorum J^. 5, and B. terrester Z. 5) and 3 po-dvg. hover-flies i. Eristalis 

 arbustorum Z. ; 2. Syritta pipiens Z. ; 3. Syrphus balteatus Deg. 



2046. V. Thapsus L. (Sprengel, ' Entd. Geh.,' p. 121; Herm. Mailer, 

 p. 430; MacLeod, Bot. Jaarb. Dodonaea, Ghent, v, 1893, pp. 340-1; Kirchner, 

 'Flora V. Stuttgart,' p. 576.) The flowers of this species are only half as large as 

 those of V. thapsiforme, and of a brighter yellow. Darwin's experiments show 

 that automatic self-pollination is completely eflFective. 



Visitors. Herm. Miiller gives the following list. 



A. Diptera. Syrphidae: all po-dvg.: i. Ascia podagrica /*. ; 2. Helophilus 

 floreus Z. ; 3. Syritta pipiens Z, B. Hymenoptera. (a) Apidae : 4. Andrena 

 parvula jK". S, apparently skg. ; 5. Apis mellifica Z. 5. po-cltg. ; 6. Bombus hortorum 

 Z. 5. do. ; 7. B. scrimshiranus K. $, do. ; 8. Halictus cylindricus F. $, apparently 

 skg.; 9. H. smeathmanellus A'. 5, po-cltg. {d) Vespidaex 10. Polistes gallica Z. j, 

 apparently skg. (Thuringia). 



The following were recorded by the observers, and for the localities stated. 



Knuth, po-cltg. humble-bees (Bombus agrorum F.), and po-dvg. hover-flies, 

 (Syritta pipiens Z., and Syrphus ribesii Z.). von Fricken (Westphalia and East 

 Prussia), 2 Curculionid beetles Cionus verbasci F., and C. thapsus F. Redten- 

 bacher (Vienna), the Curculionid Cionus blattariae F. Heinsius (Holland), the 

 po-cltg. humble-bee Bombus terrester Z. 5> and the po-dvg. hover -fly Syritta 

 pipiens Z. (Bot. Jaarb. Dodonaea, Ghent, iv, 1892, pp. 57-9). 



3047. V. phlomoides L. As long ago as the forties it was noticed by 

 Gartner that the stamens of this species degenerate (and also those of V. nigrum Z., 

 V. Blattaria Z., V. blattarioides ?auct., V. phoeniceum Z., and V. speciosum Schrad.). 

 Schulz describes the species as gynomonoecious, rarely gynodioecious ; while Comes 

 says it is self-fertile. {Cf. also the remarks of Maury under V. thapsiforme.) 



3048. N. Lychnitis L. (white-flowered type). (Herm. Mailer, ' Fertilisation,' 

 p. 430, 'Weit. Beob.,' Ill, pp. 26-8; Kirchner, 'Flora v. Stuttgart,' p. 577.) The 

 flowers of this species are homogamous and devoid of nectar. The lowest corolla- 

 lobe is the longest, and the two upper ones the shortest, but in spite of this the 



