Rosaceæ. 



35 



branched (Fig. 13, В, D). The thickness of the leaf was about 

 140 /i and the proportion between the leaf-thickness and the 

 thickness of the palisade parenchyma was |. Some weak bast 

 occurs upon the under side of the main bundle of the leaf and 

 also at the leaf-margin when a bundle runs along the latter. 

 The diameter of the flower is somewhat large, Wolf 

 records 18 — 20 mm.; the petals are broader than long and 

 yellow in colour, and these large, conspicuous bowls doubtless 



Fig. 13. Potentilla Vahliana (Godhavn on Disco). 



Ä, Transverse section of a leaf-lobe, the edges are revolute, the lower surface is tomentose. 

 JS, Transverse section of leaf ; st., stoma. C, Epidermis of the upper surface ; fi, cross section 

 of a hair which is standing on a small stalk. D, Section of spongy parenchj'ma parallel to 

 the surface. E, Glandular hair from the lower surface of the leaf. F, A highly projecting 

 stoma which was found behind the revolute leaf-edge. (A, about '^Vi ; B, C, D, E und F-*'^li). 



readily attract insects. Warming states in his notes that 

 honey is secreted abundantly. According to Warming's 

 notes, of the 20 stamens the episepalous are longer than the 

 epipetalous and stand more erect against the pistils. To 

 judge from my alcohol material Pot. Vahliana appears to be 

 homogamous, and self-pollination probably takes place. 



Flowering begins in July; according to Simmons it lasts 

 only a short time. Fruit is set abundantly (Simmons). 



