1 6 Anis in Relation to Flozvers. [Sess. 



nectar, may be mentioned the fact that certain Acarids of more 

 or less degenerate structure attach themselves to Ants. Lord 

 Avebury tells me that one he had observed lived about what 

 one may term the " neck " of some of the Worker- Ants. When 

 the Ant stoops forward to feed on some nectar the Mite comes 

 forth from its retreat and feeds on the nectar at the same time 

 as its host. This is an unusual form of commensalism. 



It is not necessary to go further into the evidence bearing 

 upon the fondness of Ants of all kinds for nectar, as the fact is 

 now generally well known to all who take even a casual interest 

 in the ways of these little folk. But we may well pass in 

 review here what is the use of nectar to the very many plants 

 which secrete it, even though, to most people with a taste for 

 Natural History, those reasons have long been known. 



To bring about the development of the seeds of a plant, it is 

 necessary that the pollen from the anthers of the ilower shall 

 come into contact with the stigma, which is connected with 

 the ovary where the embryo seeds are formed. It matters not 

 how the contact is brought about so far as the fertilisation of 

 the seeds is concerned, and it may be effected simply by the 

 pollen being transported even by the wind from the anthers to 

 the required position within the same individual flower, or 

 from one flower to another on the same plant. But large 

 numbers of experiments have proved that in the great majority 

 of cases seeds so fertilised do not give rise to plants either as 

 numerous or as full of natural vigour as those which have been 

 fertilised by the transference of pollen from another plant of 

 the same species. It has to be remembered in this connection 

 that the conditions which determine the survival of a particular 

 species of either animal or plant are very complex, and are 

 usually opposed by other conditions which tend in the opposite 

 direction. It may indeed be said of most organisms, plants 

 included, that their struggle for existence is very keen, and 

 that the chances that a given individual will survive are al- 

 most exactly balanced by the chances that it will not. A 

 very slight difference will, and commonly does, serve to turn 

 the scale either way. Hence the plant which produces good 

 seed in fair abundance will leave more descendants than one 

 which has been less favourably circumstanced in that respect ; 

 and the one that leaves more descendants will be more sure, 



