PLATE LXXI. 



Page. 

 Fig. 1. Syringothyris carteri 558 



a. Dorsal valve of a specimen from Yellowstone National Park, drawn from an 



impression of a natural mold. 

 Madison limestone, limestone bluff south side of Soda Butte Creek, northwest 

 of Abiathar Peak, Absaroka Range. 



b. Anterior view of an entire example of the same species; after Meek; figured by 



that author as Spirifer (Syringothyris) cusjiidatus. 



c. Cardinal view of same, showiug high area and foramen, and, within the latter, the 



transverse septum and internal tube; likewise after Meek. 

 Lower Carboniferous ( f ), White Pine district, Nevada. 

 Fig. 2. Semin u la madisonensis n. sp 563 



a. Dorsal view of type specimen. 



b. Side view of same. 



c. Interior of a ventral valve, showiug hinge teeth, pedicle cavity, and posterior and 



anterior adductors. 

 Madison limestone, head of Conant Creek, Teton Range. 

 Fig. 3. Seminula madisonensis v&r. pussilla u. var 564 



a. A r entral valve of type specimen, showing shape, enlarged. 



b. Lateral view of same. 



Madison limestone, Crowfoot Ridge, Gallatin Range, bed 28. 

 Fig. 4. Seminula subtil ita 564 



a. Dorsal view of a characteristic specimen from the type locality, for comparison 



with Seminula madisonensis. 



b. Side view of same. 



c. Anterior view of same. 



Upper Carboniferous, near Weston, on the Missouri River. 



Fig. 5. Seminula immature, n. sp 566 



a. Dorsal view of a specimen with the ventral beak broken. 

 6. Side view of same. 



c. Dorsal view of another specimen which is somewhat crushed. 



d. Side view of same. 



Madison limestone, west of Antler Peak, Gallatin Range. 

 Fig. 6. Seminula humilis n. sp 565 



a. Dorsal view of a rather large specimen. 



b. Side view of same. 



c. -Dorsal view of a smaller specimen from the same locality. 



Madison limestone, Crowfoot Ridge, Gallatin Range, upper part of bed 27. 



Fig. 7. Athyris lamellosa 561 



a. Ventral view of a badly exfoliated specimen. 



Madison limestone, Yellowstone National Park. 



Fig. 8. Cliotliyris crassicardinalis 567 



a. Dorsal view of a specimen showing the usual characters of size and shape, but 

 almost completely exfoliated. 

 Madison limestone, north of Owl Creek, northeast slope of Teton Range. 

 598 



