138 Mr. R. Gurney on the Copepod 
uncommon in Hickling Broad and Horsey Mere where the 
water is slightly brackish*. It is probably widely distri- 
buted in the Norfolk Broads District wherever there is a 
trace of salt in the water, since I have also found it in 
Barton Broad and in the River Ant below Irstead. It also 
occurs in Calthorpe Broad, which is a very small Broad, 
not connected with the river, in which the water is, I 
believe, quite fresh. I have failed to find it in Sutton, South 
Walsham, and Ranworth Broads. 
Mr. Scourfield has sent me a sketch of an Harpacticid 
found by him at Littlehampton this year which undoubtedly 
belongs to this species, so that it is probable that it is 
generally distributed in brackish water wherever the vegeta- 
tion provides a suitable habitat. I have found it in the 
decaying leaves of Sparganium ramosum and Scirpus lacustris, 
but it seems to prefer to live under the leaf-sheaths of the 
dead stems of Typha angustifolia. I have not hitherto been 
able to make any observations on its life-history, since I 
have only once seen an egg-bearing female and have met 
with only two immature individuals, both of these being in 
late Cyclopid stages. It seems probable that the eggs are 
not carried in egg-sacs, but are laid freely, and that possibly 
reproduction is mainly confined to the spring or early 
snmmer, Against this supposition is the fact that the males 
always have developed spermatophores in the vas deferens. 
D Arcythompsonia scotti, sp.n. (Pl. VIL.) 
Body similar in shape to D. jairliensis, Scott, with soft 
cuticle without markings. The anal operculum of the 
female is scarcely prominent and somewhat pointed, while 
that of the male, as in D. fairliensis, is deeply cleft and 
projects as a pair of conspicuous hooks (Pl. VII. fig. 10). 
The furcal rami in both sexes are tapering, not contracted 
at the end as in D. fairliensis, with a single large terminal 
seta which is not jointed as it is in Cylindropsyllus levis. 
The second abdominal segment of the male has a median 
sucker-like projection on the dorsal surface, which appears 
to be crowned with a striated horseshoe-shaped membrane 
{PL VIL. fig. 21); 
The first antenna in both sexes consists of six joints, with 
no marked division between basal and distal parts, the large 
zesthete being borne by the third joint in the female and 
by the fourth in the male. In the latter the fourth joint 
* The salinity is very variable, ranging from about 40 to over 70 
graine of chlorine as chlorides per gallon, 
