PLATE V. 



(All the figures are of the natural size except fig. 6b, which is magnified three 

 and a half times, and 7 c and 7 d.) 



Fig. 1. — Geratiocaris Pardoeana, La Touche. Carapace (with rostrum), six (?) 

 segments, and proximal portion of the caudal appendages. Ludlow Mus. (Page 

 30.) 



Fig. 2. — The same. Carapace and six segments, with the proximal portion of 

 the caudal spines. Ludlow Mus. (Page 31.) 



Fig. 3. — G. Murchisoni (Agassiz). Caudal spines, imperfect. Ludlow Mus. 

 (Page 19.) 



Fig. 4. — C. tyr annus, Salter. Four segments and imperfect caudal appen- 

 dages. Ludlow Mus. (Page 24.) 



Fig. 5. — G. gigas, Salter. Ultimate segment. Ludlow Mus. (Page 25.) 



Fig. 6.—G. Halliana (r), T. R. J. & H. W. Small. 6 a. Carapace, eight 

 segments, and caudal spines, imperfect. (Possibly G. tyrannus.) Ludlow Mus. 



6 b, part of a segment enlarged (3^ diameters) to show the ornament. (Pages 22 

 and 29). 



Fig. 7. — Xiphocaris ensis (Salter). 7 a, the telson ; 7 b, its sectional area; 



7 c, enlarged border of the convex edge ; 7 d, enlarged border of the concave 

 edge. (Page 65.) 



