COMPOSITAE 



579 



hairs, remain permanently apposed, and project far out of the florets, their only 

 function being to brush the pollen-masses out of the anther-cylinder. Here, there- 

 fore, we have a third different kind of stock ; the two others have already been 

 described. 



The pollen-grains are white, roundish to ellipsoidal, up to 37 /x long and 31 /* 

 broad, with long spines adapted to secure adhesion to the stigmatic papillae. 



Fig. 194. Petasites albus, Gaertn. (after Herm. Muller). A. Sexual floret from a female head 



{ov, raptured ovary with projecting ovule). A'. Upperpart of a corolla. B. Nectar-secreting floret of 

 the female head. C. Ditto, split longitudinally. D. Sexual nectar-secreting floret from a male head. 

 5". Part of a stylar branch from the same floret. F. Degenerate floret from a male head. (./4-Z? and 

 F y. T, E y. 80.) a, anther-cylinder; CO, corolla;,;?, filament; gr, style; n, nectary; ov. ovary. 



Visitors. — The following were recorded by the observers and for the localities 

 stated, — 



Knuth (Kiel), the honey-bee. Warnstorf (Ruppin), do. Wiistnei (Alsen), the 

 humble-bee Bombus terrester L. Alfken (Bremen), 2 humble-bees — i. Bombus 

 lucorum Z. 5; 2. B. pratorum L. 5. MacLeod (Belgium), 5 bees, 3 Lepidoptera, 

 and small flies. Burkill (Yorkshire coast), a midge (Chironomus sp.), a bug (Hetero- 

 cordylus sp.), and 2 bees (Andrena gwynana K. 5, and Bombus terrester Z.), skg. 



p p 2 



