tgt4' WhItehouSE. — The Nalural History of Planarians* 47 
I would bring this paper to a conclusion by a very brief 
reference to that subject so extensively advanced in recent 
years by American workers from studies on planarians ; 
I refer to the subject of regeneration. Planarians re- 
produce their kind exactly as do other animals by means of 
the fertilized egg ; however, they may adopt another 
method, common enough it is true, known as spontaneous 
division. It may occur by accident or by the deliberate 
action of the worm itself ; but whatever the cause, the 
animal merely becomes cleft in two, and each part builds 
up the missing portion, two perfect animals resulting. 
Such a method is quite normal ; in fact some species lay 
eggs in winter and continue reproduction during summer 
by constricting and freeing portions of the body. Some- 
times the weirdest forms result from this method of repro- 
duction and from regeneration, which suggest that the 
animal had changed its mind during the process ; we find 
wiseacres with two heads, and some people may be sur- 
prised that Natural Selection did not perpetuate creatures 
endowed with such a double share of intelligence ! Double- 
tailed forms are common enough — often the result of an 
accident. A particularly interesting form with two pha- 
rynges and two mouths is occasionally met with, and we can 
imagine no more self-satisfied creature. 
Queen's University, Belfast. 
IRISH SOCIETIES. 
ROYAL ZOOLOGICAL SOCIETY. 
Recent gifts include a Macacque Monkey from Dr. Kingsley O'Suliivan, 
a Marmoset from Mr. Bartlett, four Rabbits from Mr. J. J. Foley, two 
Peacocks from Mr. R. G. Nash, a Blue-fronted Amazon Parrot from 
Mr. J. P. Watson, and a number of Frogs and Toads from Prof. J. Baylcy 
Butler. A Brown Capuchin Monkey, a Grey Parrot, a Sulphur-crested 
Cockatoo, a Black-headed Conure, and a pair of Yellow-hammers have 
been bought. A young Wombat has been born in the Gardens. 
Many thousands of Salmon and Trout eggs have been received from 
the Irish Fisheries Office, and are now undergoing development in the 
Hatchery near the Tapper Pond. 
