CAPRIFOLIACEAE 523 



385. Sambucus Tourn. 



Flowers whitish in colour, often odorous ; homogamous or protogynous ; arranged 

 in large cymes. 



1209. S. nigra L. (Herm. Miiller, ' Fertilisation,' p. 290, Weit. Beob.,' Ill, 

 p. 76; MacLeod, Bot. Jaarb. Dodonaea, Ghent, v, 1893, P- 3*>9 ; Knuth, 'Bl. u. 

 Insekt. a. d. nordfr. Ins.,' pp. 80, 156; Kirchner, 'Flora v. Stuttgart,' p. 669; 

 Warnstorf, Verh. bot. Ver., Berlin, xxxviii, 1896.) The homogamous yellowish-white 

 flowers of this species are nectarless, but strongly odorous. They are crowded 

 together into large flat inflorescences, arranged in tiers, so as to be very conspicuous. 

 In spite of this, insect visitors are but few ; perhaps the pungent odour is repugnant 

 to many of them, or perhaps the booty is too small. The stamens diverge widely, 

 while the stigmas are sessile on the ovary in the base of the flower. Insects creeping 

 over the inflorescences, while devouring or collecting pollen, effect cross- and self- 

 pollination with equal facility; the 



latter also readily takes place auto- 

 matically, for the stigmas lie in the 

 line of fall of the pollen. 



Warnstorf states that the stamens 

 spread outwards in the course of 

 anthesis, and may possibly effect " TT , 



J r * Fig. 170. Sambucus nigra, L. (after Herm. Muller). 



geitonogamy. Self-pollination is also (1) Flower seen from the front. (2) Ditto, seen obliquely 

 rendered difficult by extrorse dehis- [f e fr nt - 0) Ditto, seen obliquely from behind. 



cence of the anthers. The pollen- 

 grains are pale-yellow in colour, small, ellipsoidal, densely tuberculated, up to 

 31^ long and 15-16 //. broad. 



According to Kirchner, there are nectar-secreting glands on the petioles ; and 

 these attract ants, which serve to protect the plant against animals creeping up from 

 the ground. 



Visitors. Herm. Muller observed a beetle in the Alps, and the following in 

 Central and South Germany. 



A. Coleoptera. Scarabaeidae : all gnawing the petals and other parts of the 

 flowers: 1. Cetonia aurata Z.; 2. Gnorimus nobilis Z.; 3. Oxythyrea stictica Z. ; 

 4. Phyllopertha horticola Z.; 5. Trichius fasciatus Z. B. Diptera. {a) Straiio- 

 myidae: 6. Sargus cuprarius Z., po-dvg. (Z>) Syrphidae: all po-dvg. : 7. Eristalis 

 arbustorum Z. ; 8. E. horticola Beg.; 9. E. nemorum Z.; 10. E. tenax Z. ; 

 ti. Volucella pellucens Z. C. Hymenoptera. (a) Tenthredinidae : 12. Allantus 

 nothus Klg. 



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



Knuth (Fohr), 2 po-dvg. hover-flies Eristalis tenax ., and Syrphus ribesii Z. ; 

 (Helgoland), the Muscid Lucilia caesar Z. creeping over the umbels, and effecting 

 geitonogamy. F. F. Kohl (Tyrol), the ruby-wasp Ellampus aeneus F. Rossler 

 (Wiesbaden), the moth Botys sambucalis Schiff. MacLeod (Pyrenees), the beetle 

 Cetonia aurata Z. (Bot. Jaarb. Dodonaea, Ghent, iii, 1891, p. 346). 



1210. S. racemosa L. (Kirchner, 'Flora v. Stuttgart,' p. 670; Schulz, 

 'Beitrage,' II, pp. 94-5; Kerner, 'Nat. Hist. PL,' Eng. Ed. 1, II, pp. 200, 326.) 

 Kirchner describes the flowers of this species as being protogynous, with persistent 



