456 ANGIOSPERMAE—DICOTYLEDONES 



also records it for Pola as the almost exclusive pollinator of the species, ' con- 

 stantly enjoying a dip into the flowers.' I have not hitherto succeeded in capturing 

 this rare bee, although white bryony is common in the neighbourhood of Kiel, 

 and I have repeatedly watched the flowers. Of other visitors only those that 

 suck nectar require mention as pollinating agents. For those which devour or 

 collect pollen usually visit none but male flowers, and only occasionally go by 

 mistake to one of the smaller female ones. 



Herm. Muller (H. I\I.), Buddeberg (Budd.), and myself (Kn.) have observed 

 the following. — 



A. Coleoptera. Jdephoridae : i . Dasytes sp., only on $ flowers, po-dvg. 

 (H. M.). B. Diptera. (a) Empidae : 2. Empis livida 5, skg. (H. M.). (b) Syipkidae : 

 3. Ascia podagrica F., po-dvg. (H. M.) ; 4. Eristalis tenax Z, do. (Kn.) ; 5. Rhingia 

 rostrata Z., do. (Kn.); 6. Syrphus balteatus Deg., do. (H. M.). C. Hymenoptera. 

 (a) Apidae: 7. Andrena florea F. 5 and $, skg. and po-cltg. (H. M.) ; 8. A. fulvicrus 

 A'. S, skg. (H. M.) ; 9. A. nigroaenea K. j and $, do. (H. M.) ; 10. Apis mellifica Z. Jf, 

 po-cltg. (H. M., Kn.); ii. Coelioxys simplex Nyl.'^, skg. (H. W.); 12. Halictus 

 cylindricus F. 5, do. (Budd.); 13. H. morio F. S, do. (Budd.); 14. H. sexnotatus 

 K. 5, po-cltg. (H. M.) ; 15. H. sexstrigatus Schenck 5, do. (H. M.). (h) Sphegidae: 

 16. Ammophila sabulosa Z., skg. (H. M). ; 17. Gorytes mystaceus Z., do. (H. M.). 

 (<-) Vespidae : 18. Eumenes pomiformis Z'. 5, skg. (H. M.) ; 19. Odynerus parietum 

 Z. 5, do. (H.M.). 



Schiner saw the Muscid Orellia wiedemanni j\Ig. in Austria ; Schletterer the 

 fossorial wasp Pemphredon unicolor F. at Pola ; and Handlirsch the fossorial wasp 

 Gorytes mystaceus Z. 



1080. B. alba L. (Sprengel, 'Entd. Geh.,' pp. 435-6.) — This species is monoe- 

 cious. The flower mechanism is the same as that of B. dioica. Hildebrand (Bot. 

 Ztg., Leipzig, li, 1893, p. 30) says that at first purely male inflorescences appear, 

 and ultimately purely female ones. In intermediate stages individual flowers may 

 develop female instead of male organs, and vice versa. 



Schmiedeknecht (Thuringia), Friese (Alsace, Hungary, and Switzerland), Saunders 

 and Smith (England), all record Andrena florea F. as the exclusive visitor. 



Schenck observed the following bees in Nassau. — 



I. Andrena cingulata F. ; 2. A. florea F. ; 3. A. fucata Sm. ; 4. A. labialis K. 5 ; 

 f,. A. labiata Schenck; 6. Halictus morio F.; 7. H. sexnotatus K. }. 



313. Sicyos L. 



Flowers monoecious, greenish-white in colour ; with exposed nectar, secreted 

 by a central disk. 



1081. S. angulata L. (Knuth, ' Blutenbiol. Herbstbeob.') — This species climbs 

 to a height of several metres, and bears inconspicuous greenish-white blossoms- 

 The male flowers are arranged in corymbs which gradually develop into racemes. 

 There are from ten to twenty flowers in each inflorescence, but as only one (rarely 

 two) matures at a time, the flowering period is prolonged. When the anthers have 

 shed their pollen the flower closes again and soon drops off". The male flower 

 is about I cm. in diameter, of which approximately one-third is taken up by a large 

 central secretory disk, while the remaining two-thirds are occupied by the five 

 whitish petals, that are traversed by green veins. From the centre of the disk 



