CRASSULACEAE 



425 



Friese (Thuringia) noticed parasitic bees (i. Coelioxys elongata Lep., and 2. 

 Stelis signata ///-.) and po-cltg. bees (3. Anthidium lituratuni Pz., and 4. A. punc- 

 tatum Lir.). 



997. S. boloniense Loisel. ( = 5. sexangulare L.). (Schulz, ' Beitrage,' 1, 

 P- 39-) — Scbulz states that in the }'ellow flowers of this species the stigmas arc 

 perfectly mature when the outer stamens are dehiscing. Automatic self-pollination 

 is quite possible, for the stamens bend towards the stigmas ; but would appear to 

 be seldom resorted to, since numerous insects are attracted by the 3elIow colour of 

 the blossoms, as well as by the abundant nectar, which is secreted as in S. acre. 



998. S. alpestre Mil. ( = S. repens Schkich.). (Herm. Miiller, ' Alpenblumen,' 

 pp. 82-3.) — This species is native to the high Alps. Its flowers are protogynous, 

 but the stigmas continue functional till the anthers dehisce, so that automatic self- 

 pollination is possible should insect-visits fail. (Cf. Fig. 141.) 



Visitors. — Herm. IMuUer observed zHymenoptera, a Diptcrid, and 2 Lepidoptera. 



999. S. albescens Haw. ( = S. rupestre /,.) — 



Visitors. — jMacLeod observed 2 bees (Bombus and Andrena) and a butterfly 

 (Lycaena) in the Pyrenees. 



1000. S. annuum T^. (Schulz, ' Bcitrage,' ).i. 77.) — The flowers of this species 

 are mostly pale-yellow in colour. Schulz states that wiien they open the stigmas are 



Fin. 142. .S>(y«w <7/J'fl/»;«, /.. (after l-ienn. Miiller). ^. Flower in the first (feinale) sta;^c. /j*, 'lluet- 

 eappils of tlic same, seen from without. C. Flower towards the end of the second (male) stage. /J. Flower 

 atffr fadinj^. (. 7.) <?, anther; ^, filament ; «, nectary ; tr', ovary ; ^, petal ; .y, sepal ; jY, sti;^ma. 



receptive, remaining so throughout anthesis. The anthers of tiie outer stamens 

 dehisce as soon as the flower opens, and then those of the inner ones. The stigmas 

 and anthers being close together and at the same level, automatic self-pollination 

 is at first possible, or even inevitable ; but the inner stamens curve outwards towards 

 the end of anthesis, thus favouring cross-pollination. Lindman too found the 

 flowers to be proLogynous at first, afterwards becoming homogamous and capable 

 of automatic self-pollination. Kerner sa)s that the outer stamens serve for self- 

 and the inner ones for cross-pollination. He also states that this annual species 

 hybernates by means of rosette-shaped ofl^shoois, should winter set in early and 

 prevent the ripening of fruits. 



Visitors. — Schulz observed occasional flies and Ichneumonids at Bozen. 



looi. S. atratum L. (Ricca, Atti Soc. iial. sc. nat., Milano, xiii, 1870, p. 25*); 

 Herm, Miiller, ' Alpenblumen,' pp. 79-80; Kerner, 'Nat. Hist. PI.' Fng. Ed. 1, II. 



