EXPLANATION OF PLATE 11 

 All figures natural size 

 Fig. la. Murex perangulatas, n. sp. Mouth view of type. 

 Fig. lb. Murex perangulatus, n. sp. Back view of same speeimeu. 

 Fig. 2a. Trophon coalingep.se Arnold. A small specimen. 

 Fig. 2b. Trophon coalingense Arnold. Mouth view of a young specimen. 

 Fig. 3. Turritella nova. n. sp. Type specimen. 

 Fig. 4a. Trophon magister, n. sp. Back view of type specimen. 

 Fig. 4b. Trophon magister, n. sp. Back view of a small specimen. 

 Fig. 4c. Trophon magister, n. sp. An extreme variation of this species. 



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