CONTRIBUTIONS TOWARDS A FLORA OF CAITHNESS 247 



In the more extreme cases the stamens are so greatly 

 metamorphosed as quite to assume the appearance of carpels, 

 each having a well-developed ovary, style, and stigma. On 

 making a cross section of the ovary one finds usually numer- 

 ous ovules crowded on a single placenta. Very seldom is 

 the placenta double as in the true pistil. Frequently the 

 inner surface of the connective bears near its base a placental 

 wart covered thickly with ovules. One finds at times one 

 side of the anther still producing pollen and the other meta- 

 morphosed, and bearing ovules on such a placenta as that 

 now described. The ovules produced on the modified 

 stamens vary from a rudimentary to a well-developed condi- 

 tion. In many of the flowers the true pistil differs from the 

 five or six staminal pistils around it in little save its rather 

 larger size and more regular form. All the pistils may 

 enlarge for a time ; though even the true pistil seldom 

 reaches the size of a small pea before the young fruit falls 

 off. Occasionally one meets with flowers in which one or 

 more of the staminal pistils become lobed, each lobe bear- 

 ing an ill-formed style and stigma. 



I am not aware of any record of so abnormal a condi- 

 tion as pistillody of the stamens becoming habitual on so 

 wide a scale in the potato or in any other species of plant. 

 The tendency to it certainly appears to be already habitual in 

 the " Champion " potato, and to become more marked in 

 the successive generations. 



CONTRIBUTIONS TOWARDS A FLORA OF 

 CAITHNESS. No. II. 



By Arthur Bennett, F.L.S. 



IN the "Scottish Naturalist" for 1888 Mr. Grant and 

 myself published a list of Caithness plants, using as far as 

 then possible such materials as we had in our possession. 

 Since then I have tried to gather together any matter that 

 seemed to assist in building up the records for some future 

 Flora of the count)'. 



4 D 



