PLATE I. 



Compsotlujris racofitzae. Figs. 3, 4, 5, 6, 9, 10. 



Frieleia Jialli. Fig. 8. 



Liothyrclla gp. Fig. 1. 



Magellania or TerebraieUa sp. Fig. 7. 



NeotJiyris lenticularis. Fig. 2. 



FIG. 1. LiotJty relict sp. Station 90. Off Three Kings Islands, New Zealand, 100 fms. A, B, ventral 



valves. Nat. size. 

 FIG. 2. Neotliyris lenticularis (Desh.). Station 9G. 7 miles E. of North Cape, New Zealand, 70 fins. 



A, dorsal valve : B, ventral valve. Nat. size. 

 FIG. 3. Compsotlnjris racovitzx (Joubin). A, C, E, Station 316. Off Glacier Tongue, McMurdo 



Sound, Antarctica, 190-250 fms. B, D, F, Station 194. Off Gates Land, Antarctica, 



180-200 fms. Dorsal views showing variation in shape. Nat. size. 

 FIG. 4. Compsothyris racovitzse (Joubin). Station 194, as above. Interior view of apical portion of 



ventral valve showing foramen, deltidial plates, pedicle-collar and dental plates. X 6. 

 FIG. 5. Compsotltyris racovitzfe (Joubin). Station 194, as above. Interior view of apical portion of dorsal 



valve showing type of cardinalia. X 7. 

 FIG. G. Compsathyris racovitzse (Joubiii). A, C, E, Station 316, as above. Anterior views of the three 



specimens A, C and E of Fig. 3, showing folding and variation in inflation of valves. Nat. size. 

 FIG. 7. Magellania or Terebratella p. Station 90. Off Three Kings Islands, New Zealand, 100 fms. 



Interior view of dorsal valve of specimen No. 1, showing young stage of loop (unfortunately 



broken) ; also crinkling of shell margin. X 6. 

 FIG. 8. Frieleia lialli, Dall. California, 822 fms. (Brit. Mus. 1918.6.8.1. Presented by J. W. 



Jackson.) Interior view of apical portion of dorsal valve showing type of cardinalia. For 



comparison w^ith Compsothyris racovitzse, Fig. 5. x 7. 

 FIG. 9. Compsotlnjris racovitzee (Joubiu). Station 194. Off Gates Land, Antarctica, 180-200 fms. View 



of portion of dorsal valve showing the undermining of external surface by boring organisms 



(seep. 190). X 100. 

 FIG. 10. Compsothyris racovitzee (Joubin). Station 316. Off Glacier Tongue, McMurdo Sound, 



Antarctica, 190-250 fms. View showing shell-mosaic and two radii (seen through the shell 



from the inside), about middle of ventral valve. X 175. 



