PLATE XXVI. 



Page 

 Dolatoceinus Maeshi Lyou 312 



Fig. la. The type specimen; posterior view. (Coll. S. S. Lyon.) 

 lb. Dorsal aspect of same specimen. 

 le. Ventral aspect of same. 

 Id. Inner floor of the inverted basal cup, showing its derivation from 3 plates. 



Dolatoceinus glyptus Hall 317 



2a. The type specimen ; posterior view. (Am. Mus. Nat. Hist. N. Y.) 

 25. Basal aspect of another specimen. (Coll. J. M. Clarke.) 



Dolatoceinus lieatus Hall 319 



3. A somewhat flattened specimen. (Am. Mus. Nat. Hist.) 



Dolatoceinus tbiadactylus Barris 316 



4a. The type specimen ; anterior view. (Museum Davenport Acad. Sci.) 



ib. Another specimen, giving a posterior view of the calyx. (Same collection.) 



4c. Another showing the dorsal view of calyx. (Coll. W. and Sp.) 



M. Ventral aspect of the same specimen. 



Dolatoceinus icosidactylus W. and Sp 319 



5a. Dorsal aspect of calyx. (Coll. V. W. Lyon.) 



5b. Posterior view of the same specimen. 



5c. Ventral aspect of same. 



5d. Dorsal aspect of another specimen. (Coll. W. and Sp.) 



Dolatoceinus lacus Lyon 311 



6a. The type specimen ; anterior view. (Coll. Sidney S. Lyon.) 

 6b. Dorsal aspect of the same specimen. 

 6c. Ventral aspect of same. 



Dolatoceinus excavatus W. and Sp 321 



7. Inner floor of the ventral disk. (Coll. V. W. Lyon.) 



8. Inner floor of basal disk. 



