194 ANGIOSPERMAE—DICOTYLEDONES 



Nectar is secreted by a fleshy disk below the ovary, stored in the corolla-tube 

 (2-3 mm. long), and protected from the entrance of rain-drops by a ring of white 

 hairs. Many insect visitors are attracted by the long conspicuous inflorescences with 

 their blue-violet flowers. Owing to protandry or protogyny, and the projection of 

 the stigma beyond the anthers in the mature stage, these visitors regularly effect 

 cross-pollination. 



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

 stated. — 



Knuth, the honey-bee, 2 humble-bees, a Lepidopterid, and 3 hover-flies. Harm. 

 Mtiller (Westphalia), 2 bees (Apis mellifica L. 5, skg. and po-cltg., and Prosopis 

 communis Nyl. 5 and $, freq., skg.) and 3 fossorial wasps (i. Psammophila viatica 

 Z. S, skg. ; 2. Cerceris labiata F. j and S, freq., skg. ; 3. C. quinquefasciata Rossi, 

 skg.): (Thuringia), a hawk-moth (Zygaena carniolica Scop., skg.): (Alps), the 

 honey-bee, and the humble-bee Bombus alticola Krchb. 5, skg. Gerstacker (Bozen), 

 3 bees — I. Xylocopa cyanescens Brull.; 2. X. valga Gerst.; 3. X. violacea Z. 

 (Ent. Nachr., Berlin, 1872, p. 272). Friese (Hungary), the bee Andrena braunsiana 

 Friese 5 freq., 5 rare. Schletterer (Tyrol), 5 bees — i. Andrena pectoralis Per., 

 very rare ; 2. Bombus argillaceus 6'co/i. ; 3. B. variabihs Schmiedekn ; 4. Halictus 

 major Nyl. ; 5. Xylocopa valga Gerst. von Dalla Torre (Tyrol), 2 bees — Halictus 

 major Nyl. 5, and Xylocopa violacea Z., 5 and S. Alfken (Bozen), the Scoliid Scolia 

 hirta Sckr. } and J, not infreq., skg., and the bee Xylocopa violacea Z. 5, po-cltg. 



2123. V. serpyllifolia L. (Herm. Miiller, ' Fertilisation,' pp. 443-4 ; Kirchner, 

 ' Flora V. Stuttgart,' p. 590 ; Warnstorf, Verb. bot. Ver., Berlin, xxxviii, 1896.) — The 



whitish flowers of this species are traversed 

 by veins of a bluish colour. Though 

 usually homogamous, they are sometimes 

 protogynous, or, according to Warnstorf, 

 protandrous. The stamens are tolerably 

 close together above, and on either side 

 the stigma, towards which the dehiscing 



Fig. 299. Veronica serpyllifolia. L. (after -j r i_ i_ 



Herm. MiiUcr). (i) Flower seen from the front, sides 01 the anthers are tumed, somctimes 

 d!FepST'" "' '^°' "' '"^'"'' ' *' "^"""' ' '' '^'^'' ■• eff'ecting automatic self-pollination. Warn- 

 storf, however, asserts that the stamens 

 project beyond the style, and turn downwards in the open flower during dehiscence, 

 so that autogamy is rendered very difficult or entirely excluded. Owing to the close 

 proximity of the stigma and anthers, insect visitors can effect self- as well as cross- 

 pollination. 



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

 stated. — 



Herm. Miiller (on flowers kept in a room), the Muscid Calliphora erythrocephala 

 Mg., skg.; Scott-Elliot (Dumfriesshire), a Muscid ('Flora of Dumfriesshire,' p. 128). 



2124. V. aphylla L. (Herm. MuUer, 'Alpenblumen,' pp. 270-1 ; Schulz, 

 ' Beitriige,' II, pp. 117-18.) — The flowers of this species agree with those of 

 V. Chamaedrys in colour, nectar-guides, and the form of the stamens. They are 

 feebly protogynous. Although the bases of the filaments are attenuated, insects, 

 which pay visits in sunny weather, touch the anthers and stigma indiscriminately, 

 effecting either cross- or self-pollination. The latter inevitably takes place in dull 



