WITH DESCRIPTIONS OF NFAV SPECIES 35 



on the tarsus ; these setae are about as long as the depth of 

 the latter joint. 



Cera. — The cercus is considerably shorter than the last leg, 

 and about the same relative length and depth as in delicatula. 

 The setae are not very closely set, and there are no con- 

 spicuous outstanding ones on either margin ; the setae are 

 comparatively short, about one-third as long as the depth of 

 the cercus, and several are slightly but by no means con- 

 spicuously longer than the others. The apical seta is longer 

 than the upper margin of the terminal area. 



Habitat. — One ten-legged specimen found under a small 

 stone embedded in clayey soil on the sea banks near Hart, 

 Co. Durham, with S. subnuda and the small wood-louse 

 Haplophthalmus mengi. S. horrida is most closely related to 

 vulgaris, but is easily recognised by its distinctive chaetotaxy. 

 The setae of the scuta are fewer and comparatively speaking 

 exceptionally long, whilst the outstanding hairs on the under- 

 side of the cercus are not present. No other described species 

 possesses the exceptionally long setae seen on the scuta of 

 horrida, this character suggesting its specific name. 



BB. — Setce on scuta normal; second scutum with about seven 071 the 

 lateral margin and two on the inner margin of process between 

 the setce before specified. Cerci with a few long outstanding seta 

 on lozaer margin only. Three dorsal setce on tarsus of hind leg. 



Scolopendrella vulgaris Hansen. (PI. I., figs. 18-20.) 



Northumberland. — Wylam, Newcastle. 



Durham. — Not uncommon in the Derwent Valley, at Gib- 

 side, Winlaton Mill, Winlaton, and Axwell Park; Sunderland. 

 Common on the Wear at Hylton, Penshaw, in Lambton Park, 

 and at Leamside ; in a dene at Fencehouses ; a few on the 

 banks of the Tees at Barnard Castle, and not uncommon on 

 the Durham side of the Tees at Piercebridge. 



Yorkshire. — Common under stones by the river side below 

 Aysgarth Falls and near Redmire, in Wensleydale, June 3rd, 

 191 1. 



