196 ANGIOSPERMAE— DICOTYLEDON ES 



by Warming in Denmark. Schulz states that — in the Riesengebirge — protandrous 

 and protogynous flowers sometimes occur on the same plant. Besides hermaphrodite 

 flowers, female ones have now and then been observed, distributed gynodioeciously 

 (Ludwig), or more frequently gynomonoeciously (Schulz). Kerner describes the 

 variety longtrosire Wichura as protandrous, and in this also autogamy takes place 

 when the flowers close. 



Visitors. — Harm. Miiller observed several flies — Syritta pipiens Z., Empis 

 livida Z., and Melithreptus scriptus Z. J. 



Verhoeff" noticed the following in Norderney. — A. Coleoptera. Carabidae : 

 I. Amara familiaris Z'zi/'A B. Diptera. {a) Empidae: 2. Hilara quadriviitata iW^. 

 S and }, freq., skg. {b) Muscidae: 3. Anthomyia sp. ; 4. Aricia incana Wiedem., skg. 

 and po-dvg. ; 5. Lucilia caesar Z., skg. (c) Syrphidae : 6. Eristalis arbustorum Z. ; 

 7. Platycheirus manicatus Afg. one S. 



MacLeod saw 2 bees and a fly in Flanders (Bot. Jaarb. Dodonaea, Ghent, vi, 

 1894, p. 168). 



Burkill (' Fertlsn. of Spring Flowers ') observed the following on the coast of 

 Yorkshire. — 



A. Diptera. {a) Muscidae: i. Helomyza sp. (p) Phoridae: 2. Phora sp., 

 skg. B. Thysanoptera. 3. Thrips sp., skg. 



485. C. semidecandrum Z. (Herm. Miiller, 'Fertilisation,' pp. 132-3, ' Weit. 

 Beob.,' II, pp. 229-30; Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 46, 151, 

 ' Bloemenbiol. Bijdragen'; MacLeod, Bot. Jaarb. Dodonaea, Ghent, vi, 1894, p. 168; 

 Kirchner, 'Flora v. Stuttgart,' pp. 241-2.) — Hermann Miiller says that the flower 

 mechanism of this species agrees with that of the last, but the flowers are even less 

 conspicuous, so that insect-visits are still fewer, and the protandry less distinct. 

 The flowers may even be quite homogamous (Schulz). In the absence of visitors 

 automatic self-pollination regularly takes place. The inner stamens are devoid 

 of nectaries, and almost always vestigial, there being, with rare exceptions, remains 

 of filaments only. In dull weather the flowers remain closed. Besides hermaphrodite 

 flowers, female ones of equal size have been observed, distributed gynomonoeciously, 

 more rarely gynodioeciously (Schulz, ' Beitrage,' I, pp. 23-4). 



Visitors: — Herm. Mtiller (H. M.) and myself (Kn.) have observed the follow- 

 ing. — A. Diptera. {a) Muscidae: i. Pollenia rudis F., skg. (H. M.) ; 2. P. vespillo 

 F., skg. (H. M.). (p) Syrphidae : 3. Rhingia rostrata Z., skg. (H. M.). B. Hymeno- 

 ptera. Apidae : 4. Apis mellifica Z. 5, skg. (H. M., Kn.) ; 5. Sphecodes ephippius 

 Z. 5, busily skg. (H. M.) 



MacLeod saw 2 short-tongued bees, a Lepidopterid, and a beetle in Flanders 

 (Bot. Jaarb. Dodonaea, Ghent, vi, 1894, p. 168). 



486. C. obscurum Chaub. and 487. C. pallens F. Schultz are closely related 

 to the last species, with which they agree, according to Schulz, as regards the flower 

 mechanism and distribution of the sexes. 



488. C. tetrandrum Curt. — As observed by me on the dunes of Helgoland, 

 this species is remarkable for the variations in number of its flower-leaves. The 

 sepals and petals are usually in fours and the stamens in fives, while there are generally 

 four carpels, though these may be reduced to three. 



The flowers, when expanded in the sun, have a diameter of 3 to 4 mm., and 

 are as high as broad. The petals are greenish and thickened at their bases, where 



