28 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



PAGE 



Fig. 3. Lepidodiscus alpcmnsis, new species 20 



The type, X 4, incrusting a large Chonctcs. Four rays curved 



to the left and the right posterior to the right, with strongly 



imbricating ambulacrals, are characteristic. 



Traverse (Presque Isle division of Long Lake formation) : 



Quarry, Alpena Portland Cement Co., Alpena County, Michigan. 



Fics. 4-6. Discocystis (Agelacrmus) kaskaskiensis (Hall) 21 



(See also pi. i, figs. 4, 5; pi. 7, fig. 11.) 



4. A normal compressed theca, X 1-3, illustrating arrangement of 

 ambulacra and mosaic interambulacrals. 



5. An abnormal theca, X 1-3, with only four ambulacra. 

 Chester (Ste. Genevieve) : Huntsville, Alabama. 



6. Aboral side of theca, X i-3, showing the narrow opening of the 

 attached portion, the fused plates of the basal surface, the 

 mosaic arrangement of the interambulacrals, and the single 

 row of flooring ambulacral plates. 



Chester (Glen Dean) : Grayson County, Kentucky. 

 Figs. 7, 8. Discocystis landoni, new species 21 



7. A complete, although crushed theca, X i-3, exhibiting the 

 strongly curved ambulacra, numbers i and 5 encircling the 

 anal area. 



8. Another specimen, X i-3, exhibiting the anal area and its en- 

 circling ambulacra more clearly. 



Kinderhook (Gilmore City) : Gilniore City, Iowa. 



Fig. 9. Hcmicystites (Lebctodiscus) chapmani (Raymond) 11,12 



The well-preserved type, X 3, exhibiting particularly the long 



series of ambulacral plates. 

 Trenton (upper part Prasopora zone) : Near Jackson Park, 

 Peterborough, Ontario. 



Fig. 10. Lebctodiscus lorifonnis Raymond 9 



Photograph of the type specimen, X 1-7, showing the strongly 

 curved ambulacra all directed to the left and the large mosaic 

 interambulacrals. 

 Middle Trenton (Cystid beds) : Ottawa, Ontario. 



Fig. II. Ciiicinnatidiscus cdencmis, new species 6 



(See also pi. 2, fig. 10.) 

 The type specimen and another individual, X 1-6, incrusting a 



ramose bryozoan. 

 Cincinnatian (Eden-McMicken) : Cincinnati, Ohio. 



Plate 4 



Figs, i, 2. Cyathocystis americanns, new species 23 



Side and top views, X 4. of the type, a solid mass of fused plates, 

 polygonal in outline, bearing the ambulacral surface at its 

 slightly convex upper broad end. 

 Chazyan (Blount-Ottosee formation) : Knoxville, Tennessee. 



