28 ANGIOSPERMAEDICOTYLEDONES 



H. de Vries (Ned. Kruidk. Arch., Nijmegen, 2. ser., 2. deel, 1875) in the 

 Netherlands noted the following. Hymenoptera. 1. Apis mellifica Z. ^; 2. 

 Eriades florisomnis L, <$; 3. Halictus leucozonius K. $>; 4. Panurgus banksianus 

 Lair, t ; a wood-wasp (Siricidae) ; Cephus pygmaeus Z. 



As visitors of R. bulbosus, Cetonia hirtella Z., was observed by Loew in 

 Brandenburg (' Beitrage,' p. 38) ; the bee Andrena humilis Imt., by Schmiedeknecht 

 in Thuringia ; the bee Andrena cingulata F., by Schenck, in Nassau ; and the 

 bee Eriades florisomnis Z. $, by H. de Vries, in the Netherlands (Ned. Kruidk. 

 Arch., Nijmegen, 2. ser., 2. deel, 1875). 



MacLeod observed in the Pyrenees (Bot. Jaarb. Dodonaea, Ghent, iii, 1891, 

 p. 387-8): 3 short-tongued Hymenoptera, 2 Lepidoptera, one of the Syrphidae, 

 and 3 Muscidae. 



In Dumfriesshire (Scott-Elliot, ' Flora of Dumfriesshire,' p. 5) there have been 

 observed Apis, one humble-bee, one saw-fly, and 2 Muscidae. 



61. R. Lingua L. (Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 18-20; 

 'Blutenbiol. Beob. a. d. Ins. Riigen') has been studied by myself on Fohr and at 

 Kiel. The stem is branched above and one metre high. It bears a number of 

 large golden-yellow flowers, with a diameter of about 4 cm., so that the plant is 

 conspicuous at a distance. Each petal bears at its base a large richly secreting 

 nectary. The flowers are protogynous. After the numerous stigmas have matured 

 centripetally, the anthers dehisce extrorsely in similar order. The stamens bend 

 outwards towards the expanded petals as they ripen, so that automatic self-pollination 

 is rendered very difficult. But owing to the oblique position of the flower it can 

 take place, though it appears to be ineffective, for frequently but few ( fruits are formed, 

 and not rarely none at all. Cross-pollination is effected by the agency of flies, 

 which nearly always alight on the middle of the flower, so that if already covered 

 with pollen they dust the stigmas on their way to the anthers and nectaries. 



Visitors. I observed the following in Schleswig-Holstein. Diptera. (a) 

 Muscidae : 1. Aricia incana Wied., nect-lkg. and po-dvg. (Fohr) ; 2. Small Muscidae, 

 as before ; 3. Calliphora erythrocephala Mg. (Kiel) ; 4. Lucilia caesar Z., as before ; 

 5. Sarcophaga carnaria Z., as before (Fohr). (&) Syrphidae : 6. Eristalis arbustorum 

 Z.; 7. E. tenax Z.; 8. Rhingia rostrata Z.; 9. Syrphus balteatus Deg.; 10. S. ribesii 

 Z.; 11. Syritta pipiens Z., all skg. and po-dvg. 



Besides these I observed in the island of Riigen. A. Diptera. Odontomyidae : 

 1. Chrysomyia formosa Scop., skg. B, Lepidoptera. Hesperidae: 2. Hesperia 

 lineola 0., skg. 



62. R. hybridus Biria. Schulz states that this species is homogamous, or 

 slightly protandrous, in the Tyrol. The flowers vary greatly in size and in the 

 number of the stamens. Schulz also observed gynomonoecism. 



63. R. auricomus L. (Sprengel, 'Entd. Gen.,' p. 294; Herm. Miiller, 'Fer- 

 tilisation/ pp. 78-9; Knuth, Bloemenbiol. Bijdragen'; MacLeod, Bot. Jaarb. 

 Dodonaea, Ghent, vi, 1894, p. 179.) The flowers agree in structure with those of 

 R. Flammula, but the corolla is rarely quite regular, almost always some or all 

 the petals are reduced, and they may even be entirely absent. The broad yellow- 

 margined sepals therefore take over the duty of attracting insects. The nectaries 

 are very variable in shape, as a rule they are pits devoid of covering-scales. Hermann 

 Miiller has represented various forms of nectary in the following diagram (Fig. 9). 



