1g01-1902.]| Zhe Entomostraca of Mid-Lothian. 319 
each other closely in general outline, and can only be dis- 
tinguished by slight differences in the anterior antenna, &c. 
Scapholeberis mucronata we have found in only three 
localities, but each time in considerable numbers. It is a 
curious-looking little creature, very dark brown or almost 
black, with greenish eggs, and antennas tinged with pink. 
Simocephalus vetulus is one of the commonest of the 
cladocerans, and may be obtained all the year round. It 
often occurs in large numbers, especially in muddy water. 
Daphnia pulex has the same apparent preference for muddy 
water; there must be many thousands in the small pond at 
Drylaw, where we have seen them swimming about in shoals. 
We found an immense number one January evening in a pond 
at Lasswade. They are often coloured bright red, and when 
present in large numbers give a distinct reddish tinge to the 
water. 
Llyocryptus sordidus is a most curious creature. To begin 
with, it is so sluggish in its movements, and so thickly covered 
with fragments of muddy vegetation, that it would be hard to 
distinguish in a catch, but for its brilliant red colour. Being 
unable to swim, it drags itself about the bottom of the pond by 
means of its strong antennas. The postabdomen is large, and 
furnished with numerous delicate spines and a surprisingly 
long pair of sete. There are on the shell four or five 
irregularly concentric curves, apparently the margins of 
different layers of shell, each bordered with a fringe of 
sharp curved spines. It is very hard to get a good view 
of Ilyocryptus; we spent about an hour one morning trying 
to clean one by squirting it in and out of a dipper in clean 
water, squirting water at it, and trying to clear off its accumu- 
lation of dirt with a needle and brush. The last named 
‘method seems to be the most efficacious. The spines at the 
front of the shell, and those at the back, are different in 
structure. 
Graptoleberis testudinaria is one of the prettiest things in 
our collection, having the shell covered with a delicate tortoise- 
shell pattern, from which the specific name is taken. It would 
probably be undistinguishable to the naked eye from some of 
the Alonas, but that its mode of swimming at once betrays it. 
It is hard to say exactly what the difference is, but if one sees 
