NOTHRUS HORRIDUS. 503 



very small apophyses, bearing short, thick, villous 

 hairs just outside the main ridge ; the third of these is 

 in the above-named constriction, and the first and second 

 are nearer together than the second and third. A 

 similar apophysis and hair is placed just behind each 

 of the two diagonal ridges. Outside the lateral parts 

 of the main ridge the abdomen is concave, it then rises 

 again, forming a broad, raised, rounded margin, the 

 extreme edge of which is not the highest part. This 

 raised edge bears a few irregular, more or less trans- 

 verse ridges, and also, on each side of the body, four 

 short, thick, curved hairs. The posterior ends of these 

 raised lateral margins widen out a little and form large 

 rounded lobes or bosses which project farther back 

 than the space enclosed by the ridge ; between these 

 lobes and behind the ridge the dorsal surface of the 

 abdomen is much depressed, so as to seem scooped out 

 like the bowl of a spoon, the hind margin being thin. 

 The progaster is raised, and bears three pairs of short 

 curved hairs. Genital and anal plates large and close 

 together, the former much the wider, the latter longer 

 and coming to a point posteriorly. 



Distribution — I only know of this species from four 

 or five specimens found by Mr. Bostock in lichen on 

 Clifton Bridge, and sent to me after being mounted in 

 balsam, and one specimen found by Mr. M. J. Michael 

 at Malvern. 



NoTHRUS HORRIDUS* (Herm.pere). PI. XLYII, figs. 1 —4 



and 7—13. 



Notaspis horridus, Hermann. P. 90, pi. vi, fig. 3. 



Oribata horrida, Gervais. P. 254. 



Nothrus horridus, Koch. Uebersicht, p. 113. 



— 7nutilus, — Heft 29, fig. 18. 



— bistriatus 1 — Heft 29, fig. 21. 



— angulatus ? Bevlese. Acari, &c. Ital., fasc. xvii, fig. 5. 



— sinuatus, Kocli. Heft 29, fig. 22 ") -^j ■■ 



— runcinatus, — Heft 29, fig. 23 ) ^^J^^P^^^- 



* Horridus, rugged, horrible, hideous. 



