INTRODUCTORY PAPERS ON LEPIDOPTERA. 145 
and applies its rostrum to the extremity of the abdomen of its 
victim, but whether the Ranatra succeeds in killing the beetle 
I am not aware. I have kept a Ranatra in the same vessel with 
Dytiscus marginalis for a week or two together without the latter 
attacking it, although they have repeatedly come into actual 
contact ; but it is quite probable that if the Dytisci were hungry 
they would make short work of the Ranatra, as they do of 
Notonecte, Corixe, &c., on occasion. The curiously lengthened 
and flattened form of Ranatra linearis, together with its yellowish 
brown colour and its habit of remaining motionless and in a 
slanting position among the grass-stalks or water-weeds in its 
natural ponds, render it somewhat difficult of detection in such 
situations; I have wondered whether these peculiarities are a 
protection to the insect, from which its slow movements would 
not enable it to escape, but I have not been able to discover any 
water animal that it has to guard against. I may, however, 
mention that when a Dytiscus marginalis comes in contact with 
the Ranatra, the latter raises its fore legs as though to ward off 
the beetle. 
The imago, which I have kept within doors from June to the 
present time, shows no signs of torpidity during the winter 
months, and I have taken a specimen of Ranatra linearis from a 
pond on March 9th, from which I should infer that it may be 
found active during the whole of the year. 
Clunie House, Court Hill Road, Lewisham. 
INTRODUCTORY PAPERS ON LEPIDOPTERA. 
By W. F. Kirsy, 
Assistant-Naturalist in Museum of Science and Art, Dublin. 
No. XIV. NYMPHALIDAXA—NYMPHALIN &. 
(CALLIZONA to PYRRHOGYRA.) 
We are still treating exclusively of South American species ; 
and the three next genera, Callizona, Gynecia and Hctima are 
' widely distributed, though very poor in species, and are closely 
related to each other. Their habits are all very similar, and they 
are very fond of settling on the trunks of trees, though Hetima 
expands its wings flat, and the others sit with their wings raised. 
Gynecia Dirce is the commonest and most widely distributed of 
U 
