ROSACE A E 385 



ro. P. clypearis Schenck J, freq., po-dvg. ; 11. P. communis Nyl. J, do.; 12. P. 



signata Pz. $ and S, po-dvg. (3) Sphegidae: 13. Oxybelus bellus Dahlb., po-dvg.; 



14. O. uniglumis L. (c) Vespidae: 15. Odynerus sinuatus F. 



Herm. Miiller saw a Cerambycid in ihe Alps (' Alpenblumen,' p. 228). 

 Sickmann noticed the following Hymenoptera at Osnabriick. — 

 Hymenoptera. Sphegidae: i. Crabro cetratus Shuck.; 2. C. chrysostoma 



f.ep., freq. ; 3. C. dives H.-Sch., rare ; 4. C. leucostoma Z., infreq. ; 5. Psen atratus 



Pz., freq. 



Von Dalla Torre observed the following bees in the Tyrol. — 



I. Andrena albicrus K. $ and J; 2. Osmia leucomelaena K. S and 5; 3. 



Prosopis borealis Nyl. 5 and S; 4. P. nigrita F.\ 5. P. bipunctata Fbr. (also 



recorded by Schletterer). 



260. Kerria DC. 



Homogamous pollen flowers. 



922. K. japonica DC. — The flowers of this species are odourless and nectarless. 

 Their mechanism is described as follows by Kirchner (' Beitrage,' p. 40). The 

 anthers of the most external stamens ripen, and the stigmas mature in the bud. 

 The inner stamens are short in proportion to their nearness to the centre of 

 the flower. At first they are curved inwards, but later on become erect. The 

 markedly diverging styles attain a length almost equal to that of the longest 

 stamens. Self-pollination is therefore inevitable, and apparently takes place even 

 before the flower opens. Focke states that the plant is self-sterile in Europe, but 

 produces succulent fruits in Central China, its native region (Abh. natw. Ver., 

 Bremen, xiv, 1897). The petals are at first of an orange-yellow colour, but become 

 inconspicuous before the innermost anthers are ripe. 



Visitors. — Kirchner did not see any. 



261. Mespilus L. 



White, conspicuous, homogamous hermaphrodite flowers ; with half-concealed 

 nectar secreted by a yellow fleshy ring in the receptacle, internal to the stamens. 



923. M. germanica L. — Kirchner ('Flora v. Stuttgart,' p. 427) states that 

 when the white flowers of this species open the five styles lie close together, but their 

 stigmas are already mature, and directed outwards. The stamens are inchned inwards, 

 and the innermost anthers are situated beneath the stigmas, while the others are 

 at the same or a higher level, and as they dehisce introrsely automatic self-pollination 

 must regularly take place. Crossing is only possible at later stages, when the 

 stamens incline more outwards and the styles curve away from one another above. 



262. Crataegus L. 



White, protogynous flowers smelling like herring-brine (of trimethylamide). The 

 nectar is half-concealed and secreted by a ring in the receptacle. On account of 

 their odour the blossoms are referred to the class of nauseous flowers, visited by 

 flies that are fond of putrefying substances. 



924. C. Oxyacantha L. (Herm. Muller, 'Fertilisation,' pp. 240-1, ' Weit. 

 Beob.,' II, p. 239; Kirchner, 'Flora v. Stuttgart,' p. 426; Loew, 'Blutenbiol. 



