EXPLANATION OF PLATE XLIV. 



Figs. 1-6 are copied from Ulrich and Bassler aud are X 30; figs. 7-19 are from 

 Jones and Kirkby and are X 25. 



Figs. 1, 2. Jonesina bolliaformis (Ulrich and Bassler). 



1. Left valve of entire carapace. 



2. Dorsal view of same showing channeled back. 



3-5. Jonesina bolliaformis tumida (Ulrich and Bassler). 



3. Left valve, incomplete at the antero-dorsal angle. 



4. Lateral view of another left valve. 



5. Ventral view of original of fig. 4. 



6. Jonesina gregaria (Ulrich and Bassler). 

 Left valve of an average old example. 



7-9. Jonesina fodicata (Jones and Kirkby). 



7,8. Two left valves showing slight variation in outline and surface 

 characters. 

 9. A right valve in which the surface is further modified. 

 10-12. Jonesina fastigiata (Jones and Kirkby). 



10. Lateral view of a right side of complete carapace. 

 11,12. Two left valves. 

 13,14. Jonesina erateri</era (Jones and Kirkby). 



Right side and ventral view of complete carapace 

 15,16. Jonesina bradyana (Jones and Kirkby). 



15. Right side of complete carapace. 



16. Ventral view of same specimen. 

 17-19. Jonesina arcuata, (Bean). 



17. 18. Two left valves showing variation in outline. 

 19. Right side of complete carapace. 

 340 



