igiy CoLGAN — Mnemic Action in Chlora perfoliata. 193 



is acquired, but not transmitted. Granting that this 

 capacity could be somehow acquired by each individual 

 plant in the few months intervening between germination 

 and flowering, the question remains, why does this capacity, 

 the capacity not merely of opening, but also of closing 

 periodically and independently of the direct stimulus of 

 sunlight, not manifest itself in a host of other species 

 exposed to precisely similar conditions ? Must we not 

 credit the germ from which the plant springs with a pre- 

 disposition to produce flowers prone to develop this peculiar 

 capacity, and must we not regard this predisposition as 

 inherited and forming part of the character of the species ? 

 Finally, the obvious objection may be made that the ex- 

 periments here recorded having been carried out on flowers 

 severed from the parent stem the results cannot be accepted 

 as valid for the complete organism, the growing plant. 

 There seems to be little weight in this objection. The cut 

 flower-heads kept in water showed a very high degree of 

 vitality, remaining quite fresh for a month and developing 

 to full bloom buds which were green when gathered. We 

 have, too, a periodic opening and closing of both the cut 

 flower-heads and the plants growing in the field and the in- 

 ference seems to be well justified that experiments on com- 

 plete growing plants would yield results in all respects 

 very similar to those here set forth. Such experiments 

 it would be by no means difficult to carry out as the species 

 is an annual of moderate size. 



Sandycove, Co. Dublin. 



NOTES. 



ZOOLOGY. 

 Colias edusa near Tramore, Co. Waterford. 



Colias edusa was not uncommon about here from the beginning 

 of September. Early in that month I took six specimens, five male, one 

 female, at Garrarus and Kilfarrissy, a few miles from here. They fly 

 very fast. The males were in excellent condition ; the female a little worn. 

 Since I have taken several more specimens : one on the 29th September, 

 of the variety helice of the female, but the front wings were worn. 



Coolfin, Portlaw, W. W. Flemynq, 



