240 MR. ROBERT GURNEY ON THE TIDES OF 
at noon on the previous day the fauna was a purely fresh-water 
one, at noon, on September 4th, it was absolutely marine, 
as shown in the accompanying list. 
LIST OF SPECIES TAKEN AT STOKESBY. 
September 3rd, 1910. 12.30 p.m., about high water. 
CLADOCERA. 
Daphnia longispina. 
Ceriodaphnia pulchei.la. 
SCAPHOLEBERIS MUCRONATA. 
Bosmina longirostris. 
Chydorus sph.ericus. 
OSTRACODA. 
Notodromas monacha. 
COPEPODA. 
Cyclops serrulatus. 
Cyclops hyalinus. 
Canthocamptus sp. ? (lost). 
Eurytemora lacinulata. 
MALACOSTRACA. 
Neomysis vulgaris. 
Pal^monetes varians. 
ROTIFERA. 
CONOCHILUS VOLVOX. 
Diatoms present. 
September 4th. 12.30 p.m., about high water. 
CLADOCERA. 
Ceriodaphnia pulchella, x sp. 
OSTRACODA. 
Not identified. 
