142 
SPOLIA ZEYLANICA. 
on to the rocks out of the water when the threatened danger had 
passed. I saw one use its wings to escape when hard pressed, but 
this is unusual.” In viewing these insects on the rocks in a small 
hillside stream at Madulsima, May 16, 1908, he observes: “The 
coloration of Gavialidium crocodilus is eminently procryptic, as it 
is also in the case of Scelimena, but the latter rests on the dark 
rocks, and usually just above the surface of the water.” On May 19 
he found this species was common in the bed of a stream on the 
Roeberry estate (about 4,000 feet elevation). Here their behaviour 
was similar to that noted above. They were found sitting locally 
on the rocks just out of the water in little colonies. “ When pressed 
they sometimes take to wing and fly out of reach, but more 
frequently dive into the water and crawl up again when the danger 
is presumably over.” Again, under date of May 26, he says : “ In 
the morning I followed up the rocky bed of a small stream and 
took a large number of S. gavialis and a few (mostly immature) 
Gavialidium .” Later on in the season at Madulsima, August 13, 
this species was found common at the waterfall. They were closely 
grouped together just above the water’s edge. A male was found 
clasping a female, but not in copulation. Two individuals had just 
completed an ecdysis and were quite soft; the cast skins remained 
beside them. In making comparison of the behaviour of Gavialidium 
crocodilus and Scelimena gavialis , Mr. Fletcher found at Madulsima, 
August 16, that “ the former species occurs usually in little colonies, 
on damp rocks near water, and is very sluggish, rarely jumping and 
never taking to wing. 8. gavialis , on the contrary, often takes to wing 
when disturbed, or very frequently dives into the water, above the 
edge of which it is usually found. G. crocodilus is not generally 
found in such close proximity to the running water itself. Still 
later in the season, on January 13, this species was found at Madul¬ 
sima. “ Along the banks of a small stream it was fairly common, 
and flew actively in the hot sunshine ; one example on being 
disturbed deliberately flew into the water and dived to the bottom. 
In one case two quite immature individuals were found on a rock 
on either side of an adult and almost touching it.” Again we are 
reminded of the difference in the behaviour of G. crocodilus and 
the species under consideration by the following observations. At 
Madulsima, January 17, 1909: “A specimen of G. crocodilus 
was taken on a rock beside a small stream ; as usual, it was very 
sluggish, and readily allowed itself to be captured in my fingers. 
Very different is the behaviour of 8. gavialis, an example of which 
was also on a rock close to G. crocodilus ; when approached with the 
hand, the Scelimena jumped off smartly and took to wing.” Under 
date of January 28, he further says : “At Labugama is a large 
artificial reservoir,which supplies Colombo with water ; this reservoir 
is surrounded by low hills, which are reserved forest—that is, no 
buildings whatever are permitted. In one part of the reservoir a 
