30 Mr. I. C. Thompson on the Copepoda 
The general agreement of my specimen with Giesbrecht’s 
description and drawings clearly demonstrates it to be 
P. bidentatus. The differmg characters of the male are as 
under. Brady supposed his specimen to be a male, but, as 
Giesbrecht points out, it certainly is a female. The latter 
authority failed to find the “stout bidentate process” as 
described by Brady as existing, produced ventrally, on the 
last thoracic segment. My specimen certainly has this 
process, though not so pronounced as in Brady’s drawings, 
and only on the right side. The left side termination, 
however, is not clearly defined, so the “ process” may have 
been lost. Length 2°75 millim. (fig. 6). Right anterior 
antenna (fig. 2) 24-jointed, the left (fig. 38) 20- “jointed, the 
latter having a geniculation between the sixteenth and 
seventeenth joints. In the right the joints after the twelfth 
are less than half the width of the previous ones. The 
relative lengths of the joints are in about the following 
proportions :— 
Right. 
123456789 10 11 12 18 14 15 16 17 18 19 20 21 22 93 24 
164 4644433 3°33 4°6' 678 10 12 1416 2a 
Left. 
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2016161616 6 8493 ows ee i Once: 
The fifth pair of swimming-feet (fig. 4) consists of two 
branches, each 3-jointed, with one common basal joint. A 
lamellated process projects from the inner side of the first 
joint on the right, and a smaller one from the inner side of 
the second joint on the left. The terminal joint of the right 
consists of a strongly muscular chelate organ, that of the 
left being rather smaller and apically obtuse and also very 
rouscular. 
Anomalocera Patersoni, Templeton. 
1837. Anomalocera Patersonii, Templeton, Tr. Ent. Soc. vol. ii. p. 34. 
It was rather surprising to find only one specimen of this 
large brilliantly coloured species, well known as occurring 
often in dense shoals round our coasts, and known also in 
the Mediterranean and in the Atlantic and Pacific Oceans. 
It was taken by the surface-net. 
Acartia Clausi, Giesbrecht. 
1863. Dias longiremis (part.), Claus, Freileb. Cop. p. 193. 
One of our commonest British species. Well known in 
