1901. Cooke-Trench. — Is the Holly dicccious ? 107 



Hooker and Arnott, "The British Flora," p. 272, "Some 

 flowers destitute of pistil." This agrees with Smith's state- 

 ment, and would be what Darwin calls andro-dicecious, of 

 which he says, speaking generally at p. 299, that such plants 

 are extremely rare or hardly exist. In the preface (p. xviii.) 

 he gives three exceptions to this rule, but the Holly is not one 

 of them. 



Perhaps the most valuable addition of late years to works 

 on systematic botany has been Kerner's " Natural History of 

 Plants." He wrote subsequently to Darwin, and therefore, 

 with a full knowledge of his researches and consequent 

 theories ; he devotes no less than thirteen pages to an 

 inquiry into the distribution of sexes. It will, by the way, be 

 a surprise to some to learn that hermaphrodite flowers, which 

 many of us have been accustomed -to look upon as the rule, 

 really comprise little more than a third of all the species of 

 phanerogamous plants. The remainder, being more or less 

 unisexual, he divides into no less than fifteen groups, giving 

 numerous examples of each, but in none of them does he 

 mention the Holly (half-vol. iii., pp. 288 to 300.) He twice 

 mentions the Holly in the course of the book, but both times 

 in relation to its leaves, not to its flowers. 



I wonder whether any of the readers of the Irish Naturalist 

 would join with me in making, during the present season, a 

 careful search amongst trees that have borne berries for flowers 

 with pollen-bearing stamens? It would be well that the 

 grains should be examined under the microscope, in order to 

 ascertain that they had at least the appearance of being perfect 

 grains. 



Darwin's conclusion that the Holly is dioecious is, as I have 

 pointed out, founded on his experience that the stamens on a 

 berry-bearing tree are " quite destitute of pollen." If, there- 

 fore, it can be shown that this is not always the case, his 

 foundations are destroyed, the superstructure comes to the 

 ground- and we are free to consider the question discharged of 

 the great authority that attaches to his name. But it does not 

 therefore follow that he was wrong. Writing of pseudo- 

 hermaphrodite flowers, Kerner mentions a number of such, 

 and adds, " they have plain well-developed ovaries, and 

 stamens in whose anthers pollen-grains are found in greater or 



