26 THE BRITISH WOODLICE. 
consideration. Platyarthrus hoffmannseggii is small and white and 
the edges of its side plates are toothed, but it is oval in shape, 
possesses no eyes, and its stout antenne have but a single joint 
to the flagellum instead of four. On the Continent this species 
has been found in rich soil, 
BRITISH LOCALITIES :— 
England: Eton; (Stebbing, 71a): Sunderland; (Brady, 50a). 
FOREIGN DISTRIBUTION :— 
Europe: France ; Wimereux and Lyons, Forét (25) : Norway ; Denmark ; (59). 
Genus—HAPLOPHTHALMUS Schobl, 1850 (66), p. 449. 
Abdomen broad (comparatively); eyes simple; flagellum with three 
joints ; back with longitudinal ridges. 
The body of Haplophthalmus is long in proportion to its width, 
but there is no abrupt decrease in the breadth of the abdomen as 
seen in Tvichoniscus and Trichoniscoides. The eyes are simple as 
in the latter genus and the lateral lobes of the head are rather 
large, while the side plates of the body are well separated. 
Haplophthalmus mengii Zaddach. Prater VII. 
1844 Itea mengti Zaddach (77), p. 16. 
1860 Haplophthalmus elegans Schobl (66), p. 449. 
1885 Haplophthalmus mengit Budde-Lund (8), p. 250 
1893 Haplophthalmus mengit Sars (59), p. 167, pl. LXXIV., fig. 1. 
The Rev. Canon Norman discovered two specimens of this 
species in Ireland in June, 1go00 (5c); in the 
previous year one of us (Mr. Webb) found a 
single example at Eton Wick. 
The main differences between the members 
of this genus and their allies are set forth in the 
generic description and incidentally elsewhere, 
so we shall content ourselves with giving the 
distinctive points of the two British species. 
Haplophthalmus mengu has a number of raised 
longitudinal ribs on each segment of the thorax, 
the outer ridges being somewhat broken. There 
are also two prominent ribs upon the third 
segment of the abdomen. 
BRITISH LOCALITIES :— 
England: Eton; (Stebbing, 71a): Sunder- 
FIG. 41.— FLAGELLUM 0 - 
AND LAST PEDUNCULAR land ; (Brady, 50a). 
OINT OF THE ANTENNA / . - . 
ae Iveland: Corcumroe Abbey; Co. Clare 
mengit. (Norman, 50). 
FOREIGN DISTRIBUTION :— 
Europe: France ; (25): Norway ; Prussia ; Germany ; Bohemia; (59). 
