318 The Entomostraca of Mid-Lothian. [Sess. 
be relied on as a constant character, often varies. We have 
found specimens with one, two, and three small spines re- 
spectively, on the inner side of the second joint. This is a 
very common species; like others of the same genus, it is in 
the habit of concealing itself among algas and moss; but, 
unlike them, it is easily dislodged 
The little ostracod Cypridopsis aculeata is mentioned by 
Brady as a species which prefers brackish water, and he notes 
its occurrence in eight localities, seven of which are slightly 
brackish, while the eighth is loaded with salts of lime. Our 
own specimens were all obtained from brackish water, with 
the exception of one, which we found in a pond on a stream 
near Balerno. 
Diaphanosoma brachyurum has a peculiar interest for us: 
in the autumn of 1900 we discovered, in a mixed collection 
from the three ponds in Penicuik grounds, the fragment of a 
creature with which we were not familiar, and which, judging 
from the antenna, we thought was most likely Diaphanosoma. 
We returned to the ponds several times, hoping to find a com- 
plete specimen, but were never successful. About a fortnight 
before the close of the competition, the number of our species 
had risen to fifty-nine, and we were very anxious to make it 
up, if possible, to sixty. We accordingly took a fishing from 
Marfield Loch, as having the most uncommon fauna of all our 
fishing-grounds; and we were rewarded by finding several 
specimens of Diaphanosoma brachyurum, the very creature we 
were most eager to obtain. Curiously enough, all the specimens 
were males. 
In the same collection we found some splendid specimens of 
Acantholeberis curvirostris. This is a very handsome creature, 
brightly coloured, and with elaborately adorned antennas and 
postabdomen. It is a fragile thing, and owing to our un- 
familiarity with it, and the short time at our disposal after 
finding it, we did not graduate it carefully enough into the 
glycerine jelly, so that our specimens are unfortunately com- 
pletely spoilt. 
Ceriodaphnia is a genus with which we have only recently 
become familiar; we recorded three species in our list, @ 
reticulata, C. scitula (?), and C. quadrangula, but are almost 
certain that we have a fourth. Several of the species resemble 
