PLATE XXIX. 



Fig. l.—Dithyrocoris Dunnii, sp. nov. A trifid tail, imperfect. Nat. size. Mus. Geol. Surv., 

 Scotland, F^'. No. 17. Larriston Burn. (Page 186.) 



Fig. 2.— Z*. Dunnii. M. G. S.Sc, F \\ No. 19. Harebow Hill Quarry, Penton, Cannobie. 

 Part of a caudal trifid. Nat. size. (Page 186.) 



Fig. 3 «1 



Fig. ,3 J 



^[d. Neihoni, sp. nov. Caudal appendages. Nat. size. Neilson | ere 187 ) 



_. I Collection, marked K. East Kilbride. 



Fig. 8 cJ 



J 



pj(T. 4, — Ehaehiira {Bithyrocaris ?) venosa, Scudder. Copied from ' Proc. Boston Soc. N. H.,' 

 vol. .xi.x, pi. ix, fig. 8. Caudal appendages, ventral aspect. Nat. size. Coal-measures, Illinois. 

 (Page 188.) 



Fig. 5a. — Didiyrocaris cnrhonaria, Meek and Wortben. Copied from 'Geol. Surv. 111.,' vol. v, 

 pi. xxxii, fio. 1 a. Caudal appendages, ventral aspect. 1 a. Coal-measures, Illinois. Nat. size. 

 (Page 190.) 



Fif. 5 h. — D. carhonaria. Sectional area of thick part of tbe stylet (part of fig. 1 a). 



Fig. Q.—B. carhonaria. Caudal appendages, dorsal aspect. Copied from M. and "W.'s fig. 1 b. 



Fitr. 7. — B. Kochi, Ludwig. Copied from ' Palfeontogr.,' vol. xi, pi. 1, fig. Iff. Devonian, 

 Herborn, DiUtbal, Nassau. Caudal appendages. Dorsal aspect. Nat. size. (Page 191.) 



Fig. S. — B. Kochi. Copied from Luduig's fig. 1. Caudal appendage. Ventral aspect. Nat. 

 size. Devonian, Herborn. (Page 191.) 



Fig. 9.—D. breviaculeata, Ludwig. Copied from ' Pal.neoutogr.,' vol. xi, pi. 1, fig. 2. Caudal 

 appendage. Ventral aspect. Devonian, Butzbacb, Nassau. (Page 191.) 



Fi<T. 10a. — D. testudinea, Scouler. An ultimate abdominal segment. Dorsal^ 

 aspect. Neilson Collection. J. East Kilbride, x 3. 



Fig. 10 J. — D. /esludiiiea, Scouler. Ventral aspect, x 3. 



Fig. 10 c.— D. <esi(«(/jHea, Scouler. Sectional area, x 3. 



Fig. 11 n. — B. testudinea, Scouler. Ventral aspect, x 3. 



Fig. 11 h. — B. testudinea, Scouler. Ornament, x 100. 



Fig. 12 ff. — B. testudinea, Scouler. Dorsal aspect, x 3. 



Fig. 12 b. — V. testudinea, Scouler. Ventral aspect. X 3. ^{.^n-ge 153.) 



Fig. 12 c. — B. testudinea, Scouhr. Sectional area, x 3. 



Fitr. 12 d. — B. testudinea, Scouler. Ornament. x 20. 



Fig. 13 n. — B. testudinea, Scouler. Dorsal aspect, x 3. 



Fig. 13 b. — D. testudinea, Scouler. Ventral aspect, x 3. 



Fig. 13 c. — D. testudinea, Scouler. Sectional are.i. x 3. 



Fig. 11. — D. testudinea, Scouler. Diagram of the lines on the outside of an 

 ultimate abdominal segment ; the dorsal lines dark and the ventral lines dotted, x 3. 



Fig. 1.5 rt. — Ptychocaris? Jaschei (Komer). Copied from ' Pala?ontogr.,' vol. v, 

 pi. ii, figs. 13 a— c. Fragment. Nat. size. Devonian, Klosterholz, Hartz. 



Fig. 15 b. — Outline of the sectional area. 



Fis;. 15c. — Magnified part of the ornament. ("(Pafe 193.) 



Fig. 16 o. — Copied from (Kayser) ' Abhandl. Kart. Preuss.,' vol. ii, Heft 4, pi. i, 

 figs. 13, 13 a. Fragment. Nat. size. 



Fig. 16 b. — Sectional area. 



