174 EXPLANATION OF PLATES. 



Fig. 3.— ORTHIS ARACHNOIDES ? 



Fig. 3 a. Shell, natural size. 

 3 h. Enlargement of strife. 



Fig. 4.— EUOMPHALUS MICHLERANUS. 

 Fig. 5.— ASAPHUS EMORYI. 



PLATE XXI. 



Fig. 1.— HOLASTER ELEGANS. 



Fig. 1 a. View of summit of specimen. 

 1 S. Base of same. 

 1 c. Posterior, profile view. 

 1 d. Lateral view, profile in outline. 



1 e. Enlargement of surface. 



Fig. 2.— TEREBRATULA LEONENSIS. 



Fig. 2 a, h. Dorsal and profile views. 



2 c. Enlargement, showing punctate character of shell. 



Fig. 3.— GRYPH^A PITCHERI. 



Fig. 3 a. View of upper side of specimen with the two valves attached. 



3 h. Exterior of the lower valve of same. 



3 c. Interior of lower valve of a smaller individual. 



Fig. 4.— PHOLODOMYA, SANCTA-SABL^. 



Fw. 5.— CARDITA SUBTETRICA. 



Fig. 6.— CAPSA TEXAN A. 



Fig. 7.— TDRRITELLA LEONENSIS. 



Fig. 7 a, I. Two views of the same individual. 



Fio. 8.— HAMITES LAKVATUS. 



