PLATE III. 



(All the figures are of natural size except fig. 4 b, which is one and a half natural 



size.) 



Fig. 1. — Geratiocaris gigas, Salter. Ultimate segment and a portion of the 

 appendages. Mus. Pract. Geol. (Page 24.) 



Fig. 2. — C. tyrannus, Salter. Four segments and the distal portion of the 

 appendages. Mus. Pract. Geol. (Page 22.) 



Fig. 3. — The same. Four segments and the proximal portion of style and 

 stylet. Mus. Pract. Geol. (Page 23.) 



Fig. 4. — G. Murchisoni (Agassiz). 4 a, four segments and appendages ; 4 b, 

 one of the segments enlarged (half as much again) to show its ornament. Mus. 

 Pract. Geol. (Page 16.) 



Fig. 5. — G. tyrannus, Salter. Small ; five segments and imperfect appendages. 

 Mus. Pract. Geol. (Page 23.) 



Fig. 6. — The same. Small ; four segments and the appendages. British 

 Museum. (Page 23.) 



Fig. 7. — G. Murchisoni (Agassiz). Two stylets. Mus. Pract. Geol. (Page 

 18.) 



Fig. 8. — G. tyrannus (?), Salter. Fragment of the anterior moiety of a right 

 valve. Mus. Pract. Geol. (Page 23.) 



Fig. 9. — G. cassioides, T. R. J. & H. W. Carapace and imperfect abdominal 

 segments. British Museum. (Page 59.) 



