222 SOME NOTES ON THE VICTORIA REGIA. 



side of the leaf is coloured violet by a pigment called anihocyatiin, 

 which is believed to change light into heat, and thereby materially 

 help to warm the leaf The leaf is pierced with numerous pores, 

 which allow the rain or other water which may accumulate upon 

 them to pass through, and thus prevent the leaf from being sub- 

 merged. The leaves are only armed with prickles on the under 

 surface and on the turned-up margin — i.e., only where they are 

 exposed to the attacks of plant-eating aquatic animals. 



It is an interesting fact that many woody plants are only pro- 

 tected while young — i.e., while they are short, and their foliage can 

 be reached by ruminants, such as goats, sheep, and oxen • but on 

 the branches beyond the reach of the mouths of these animals^no 

 prickles and spines are developed. 



I cannot close this paper without a word on a remarkable 

 companion which the Victoria Regia had in the year 1893, and I 

 will add a note which Mr. Harrow has kindly written on that 

 curious organism, the Fresh-water Medusa, Li7itnocodium Sowerbii. 

 It is as follows : — 



Ifresb^water /llbeDusa, XimnocoMu?n Sowerbii. 



By William Harrow. 



The Fresh-water Medusa which appeared in the Victoria Regia 

 tank during the summer of 1893 has proved a most interesting 

 topic to zoologists and many others, and information relating to it 

 has been widely circulated throughout the country by various 

 articles in the newspapers. 



Professor E. Ray Lankester, in a most interesting article in 

 Nature, says : — " For three years nothing has been seen of the 

 Fresh-water Medusa in the Regent's Park, and naturalists had 

 given up hope of carrying on any further investigation into its 

 life-history. It seemed as though this beautiful little organism — 

 brought, we know not how or whence, into the midst of London — 

 had, like some mysterious comet, unexpectedly burst on the zoo- 

 logical world and as unexpectedly disappeared. 



" I was, therefore, greatly astonished to hear in September from 

 my friend, the Director of Kew, that the curator of the Sheffield 

 Botanic Gardens had discovered it in a quantity in the Victoria 

 Regia tank under his care during the present summer, and I was 



