MR. R. GURNEY ON FRESH- AND BRACKISH-WATER CRUSTACEA. 645 
ClRRIPEDIA. 
Balanus sp? In the Bure, nearly opposite the Muckfleet, there 
are some piles and planking supporting the bank, 
and on these I have found large, living specimens of 
a species of Balanus. In this place, eleven miles 
from Breydon, the water is generally almost fresh. 
The nauplii of Cirripedes are often met with in the 
lower reaches of the rivers, and also in Oulton Broad, 
but I have not been able to find the adults in any 
other place than that above-mentioned. If they 
can live in the Bure in almost fresh water, it is 
surprising that they should not also live in Oulton, 
where the water is always distinctly saline. 
COPEPODA. 
Cyclops strenuus, Fischer. I have not paid attention to the 
varieties of this species, but it seems that C. rieinus , 
Uljanin, is the only form found in the Plankton of 
the Broads. The true C. xfrenuux , which is very 
variable itself, appears to be confined to the littoral 
regions and to ponds. It becomes very rare in the 
Broads themselves during the summer, and is most 
abundant in mid-winter. 
„ leuckarti, Claus. 
,, h yalinus, Rehberg. Generally regarded as a variety of 
C. oifhoiioiiles, Sars ( = C. Srourfieldi, var. Brady). 
I have not seen C. oithonoides, but C. hyalinus is 
widely distributed among the Norfolk Broads. 
,, dybowskii, Lande. Sutton, Catfield Fen, Calthorpe and 
ponds at Sprowston and Herringfleet. 
,, bicuspidatus, Claus. In brackish water this species is 
represented by the variety Lubbockii , Brady, with 
only fourteen joints in the first antenna. This 
variety occurs in the Muckfleet, apparently at all 
times, whether the salinity is high or low. 
„ languidus, Sars. I have found this species at Sutton 
only, where it lives in submerged moss. 
