1896.] ^o6 1 Smith. 



EXPLANATION OF PLATES.* 

 Plate XVI 



Fig. 1. Gi'strioccras mnrian urn Verneul 200 



1 a. Side view. 



1 h. Kear view. 



Fig. 2. G. marinnum, artificial cast, magnified twice. 



2 (I.. Front view. 



2 5. Side view. 



Fig. o. G. marianum, largest specimen. 

 8 n. Side view. 



3 &. Cross section ofwhorL 

 Fig. 4. G. marianum, artificial cast. 



Fig. 5. a, b, e. G. 'marinnum, showing the development of the sutures. 



Plate XVII. 



Fig. 1. Gastrioceras cicelsum Meek 2G0 



1 a. Side view. 



1 b. Cross section of whorl. 



1 c. Sutures. 



Plate XVIII. 



Fig. 1. Gastrioceras globulosum Meek and Worthen 258 



1 a. Side view of small specimen. 



1 b. Front view of small specimen. 

 Fig. 2. G. globulosum, artificial cast from a mould. 



2 a. Side view. 

 2 b. Front view. 



Fig. ;J. G. globulosum, sutures, enlarged twice. 

 Fig. 4. G. globulosum, cast showing surface markings. 

 Fig. 5. G. globulosum, small glohose specimen doubtfully referred to 

 this species. 

 5 (t. Front view. 



5 b. Side view. 



Fig. G. G. globulosum, small specimen showing the low flattened whorl. 



6 a. Side view. 

 6 b. Front view, 



Plate XIX. 



Fig. 1. Paralegoceras iowense Meek and Worthen 263 



1 a. Side view, partly restored. 

 lb. Front view. 



Fig. 2. P. iowense, inner whorl taken out of the large specimen shown 

 in Fig. 1. 



2 a. Side view. 



2 b. Front view. 



♦Where not otherwise stated the figures are all natural size. 



