THE FERTILISATION OF THE LARCH. 8 1 



On the whole the evidence in favour of wind-fertilisation pre- 

 ponderates, but the bright colour of the bracts and the sheltered 

 position of the ovulary stigmas are hardly capable of reconciliation 

 with this being the exclusive mode. Possibly the larch may be 

 self-fertilised as a rule, and only an occasional crossing effected 

 either by wind or by insect agency. 



It may be worth mentioning in this connection that a good 

 many wind-fertilised flowers do exhibit more or less of a dull 

 reddish tinge, such as the elm and some of the cypresses. Some 

 authors state, probably on the authority of Strasburger or Hof- 

 meister, that in coniferag the ovule at the period of fertilisation 

 exudes a drop of liquid at the micropyle, and that the falling 

 pollen is caught by this. Afterwards, by the evaporation of this 

 drop, the pollen grains are stranded on the nucleus of the ovule. 

 So far as I have been able to observe there is no such provision 

 in the larch, where indeed it would be quite superfluous, for the 

 pollen adheres very easily to the papillose expansion of the ovules, 

 whether brought by wind or any other agency. 



The fertilisation of the larch has been studied by Delpino, but 

 his papers are not accessible to English readers. (Altri apparecchi 

 dicogamici recentemente osservati. — Nuovo Giorn. Bot. Ital. II., 

 pp. 51-64, 1870.) As Miiller appears to be familiar with this 

 writer's investigations, he would most certainly have referred to 

 the circumstance had Delpino found an insect-fertilised conifer, 

 but instead of that, Miiller, as we have seen, asserts that all the 

 gymnosperms belong to the anemophilous class. In view of what 

 has just been said, however, we cannot accept this statement 

 without reservation. If further observation should bring to light 

 insect-fertilisation occurring among the gymnosperms, it would go 

 to prove that they form a group more nearly co-ordinate with the 

 angiosperms than has been supposed. Should any of the conifers 

 turn out to be adapted to crossing by insect agency, this would 

 favour the view that they had an independent origin, and are not 

 to be viewed as representing a phase in the evolution of angio- 

 spermous plants. If, however, the evidence be accepted as 

 conclusively proving larix to be anemophilous, then, assuming the 

 bracts to be protective in function, it might be possible to explain 

 their coloration on the theory that their brilliancy serves to 

 warn away birds and other enemies which might devour the young 



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