TAKEN OFF NORTHUMBERLAND AND DURHAM. 221 



and finely setose for nearly its whole length. Outer branches 

 of the swimming feet (figs. 5, 7) three-jointed, the middle 

 joint small, outer margins bearing foliaceous lancet-shaped 

 spines with finely denticulated edges, the spines arranged on 

 the various joints as follows — on the first foot i, i, 3, second 

 foot I, I, 3, third foot i, i, 2, fourth foot i, i, 2 ; besides the 

 marginal spines there is on each foot an apical spine, longer 

 than the rest, but denticulated only on the outer edge ; the 

 inner margin of the limbs setiferous : inner branches of all the 

 feet three-jointed, the third joint variable in length, but always 

 much longer than the combined lengths of the first two joints — 

 that of the first foot (fig. 5) bearing a single lancet-shaped 

 apical spine ; second foot produced at the apex into a short, 

 blunt process, and bearing on the margin near the apex two 

 slender pectinated spines (fig. 6) ; inner branch of the third 

 foot (fig. 7) having a slender produced apex, at each side of 

 which are two pectinated spines ; fourth foot (fig. 8) very 

 much like the third, but having in addition a small marginal 

 seta attached not far from the apical spines ; fifth pair of feet 

 (fig. 9 a) minute, one-jointed, with two fine apical setae. 



Only one specimen — a female — of this interesting species 

 could be found, notwithstanding a most careful search over 

 the whole gathering. I am therefore unable to confirm 

 Giesbrecht's definition as to the characters of the male. I 

 have some doubt, however, as to the three-jointed character 

 of the antennae. In my specimen there seems to be a fourth 

 (basal) joint as shown in the figure, but this is only rather 

 obscure; and it is possible that the species may, in this respect 

 also, conform to Giesbrecht's definition. 



