306 SPOLIA ZEYLANICA. 
NOTES ON CERTAIN SHORE CRABS, 
By C. T. Symons, B.A. (Oxon.), F.R.G.S. 

HE observations here recorded were made at Neerodu- 
munai, which is a few miles south of Trincomalee, at 
the outlet of Lake Tamblegam. It appeared advisable to 
put them on record, firstly, because there do not appear to be 
many records of the habits of crabs ; and, secondly, because 
there is some discrepancy in the records of the habits of one 
of the crabs mentioned. 
The shore crabs which were watched belonged to three 
distinct genera, namely, a Gelasimus, a Dotilla, and a Scopi- 
mera, the first and third of which have not yet been 
absolutely identified. 
Gelasimus.—The Fiddler or Caller crabs are well known as 
possessing one cheliped enormously exaggerated in size, and 
usually of a very distinct pink colour. This enlarged claw 
may occur on either side of the body, the numbers, so far as 
I could ascertain, being about equal for each. 
Near Neerodumunai there are three colonies of these crabs, 
and it is very noticeable that they are all situated in positions 
where the sand is comparatively muddy, only just covered 
at high tide, and not on the fine soft sand which is so abundant 
there. In one case the colony is amongst rocks, under some 
shrubs. Here the crabs are much tamer than in the more 
open colonies, presumably because a person watching them is 
mistaken for the overhanging branches. In watching these 
crabs it is very noticeable that though their sight is very 
acute, their sense of hearing appears to be very deficient. 
They remain quite undisturbed while an ordinary conver- 
sation is carried on, and I understand that even a gun-shot 
produces little effect on the colony. The situation of their 
eyes on long eyestalks renders them very efficient for keeping 
a good lookout in all directions. 
The male members of the colony do not appear to wander 
far from the entrances to their burrows. All seem to spend 
most of their time in feeding, and it was their method of 
doing this which first attracted me to this series of crabs. 
