120 BRITISH COPEPODA. 
inner branch ciliated on the upper half of the inner 
margin, but destitute of long setee ; terminal claws two, 
long, slender, and only slightly curved. “On the 
lower borders of the four last body segments, and, in 
the female, also on the lne between the first and 
second abdominal segments, a row of minute teeth. 
The last abdominal segment shorter than the preced- 
ing; the caudal segments very short and broad; the 
inner tail seta longer than the abdomen, the outer 
scarcely half as long. ‘'T'wo ovisacs.”—Claus. 
My observations of this species have not been so 
full as might be wished, owing to a scanty supply of 
specimens. Possibly it ought to come under Boeck’s 
genus Diosaccus ; but I have no doubt whatever of the 
identity of my specimens with D. minutus, Claus. They 
occurred very sparingly in a tow-net gathering, taken 
at dusk, in Westport Bay, Ireland. 
Genus 25. THatestris, Claus (1863). 
Body slender and elongated, or broad and depressed. 
Anterior antennee 9-jointed (sometimes 8- or 6-jointed, 
Boeck). Inner branch of posterior antenne 2- or 3- 
jointed. Mandible-palp large, 2-branched, the imner 
branch usually the largest. Masticatory portion of 
the maxilla provided with numerous strong teeth ; palp 
large, its terminal segment usually armed with a large 
claw; lateral segments sometimes reduced to a few 
bristles. First pair of foot-jaws ending in a strong 
