PLATE 66. 



Lepidesthes wortheni Jackson. Page 4 Hi. 



Figs. 1, 2. Keokuk Group, Lower Carboniferous, Crawfordsville, Indiana. 



Fig. 1. 1". Hnum Coll. An exceptionally clear specimen. Natural size. Eight columns of regular hexagonal plates in 

 each ambulacra! area, pore-pairs in the upper part of each plate, toward the next adjacent interambulacrum in each 

 half-area. Three columns of plates at the mid-zone in each interambulacrum. all imbricating dorsally and from the 

 .enter laterally and over the ambulacrals. The median column, as usual in the species consists of wider plates which 

 imbricate laterally in two directions, right and left, over the two adradial columns (compare Lepideslhes colletti, 

 Plate 71, fig. 1: Meekechinua elegans, Plate 76, fig. 1). Where plates are wanting in interambulacrum A, the beveled 

 edges show clearly. Drawing, Plate 67, fig. 8. 



Fig. 2. Mus. Comp. Zofil. Coll., 3,171 (from R. T. .1. Coll.). Natural size. Specimen smaller than fig. 1. Ambulacra! 

 plates are hexagonal in form. Interambulaerum A is nearly complete; tubercles very clear. Drawing, Plate ti7. 

 fig. 10. 



Fig. 3. No original label, but probably from the Keokuk Group of Crawfordsville, or that vicinity. Boston Soc. Nat. 

 Hist. Coll., 11,601, holotype. A small individual. Natural size. Ambulacra! plates are more rhombic in form 

 than in figs. 1 and 2. Interambulacrum C shows four columns of plates ventrally as a character in development. 

 Drawings. Plate fi7. figs. 9 and 12. 



Lepidesthes formosa Miller. Page" 418. 



Figs. 4-7. Kaskaskia Group, Lower Carboniferous, Pulaski County, Kentucky. 



Fig. 4. Chicago Univ. Coll., 6,604, holotype. Natural size. 



Fig. 5. Same specimen. X 1.7. Oriented by the Loven method as the madreporite is preserved. Eight columns of 

 plates in an ambulacra! area and five columns of plates in each of the interambulacra! areas al I lie mid-zone. Some 

 ocular, genital, and periproctal plates are preserved. A madreporite with fine pores is clearly seen. Drawings, 

 Plate 68, figs. 4-7. 



Fig. 6. Chicago Univ. Coll., 6,604, paratype. Natural size. Another specimen although with the same catalogue number, 

 with parts of the lantern in place. Drawings, Plate 68, figs. 8 and 9. 



Fig. 7. F. Springer Coll., 8,042. Enlarged. X 2. A very complete specimen for the ventral region. Teeth and pyra- 

 mids are in the oral area, with ambulacral plates alone on the peristome. Eight columns of plates in each ambula- 

 cral area and four columns of plates in each interambulaeral area as far dorsally as they are preserved. Drawing, 

 .Plate 68, fig. 3. 



Lepidesthes coreyi Meek and Worthen. Page 423. 



Fig. S. Keokuk Group, Lower Carboniferous, Crawfordsville, Indiana. F. Braun Coll. Natural si/e. The ambitus is 

 above the mid-zone (p. 32). There are ten to twelve columns of plates in each ambulacral area and six columns of 

 plates in each of the interambulaeral areas at the mid-zone. A very large and complete specimen. Drawings, 

 Plate 68, figs. 18-20. 



Fig. 9. Same horizon and locality. Univ. of Michigan Coll., 149, holotype. Natural size. Quite complete from the 

 ventral border to the mid-zone, but in part wanting dorsally. Ten columns of plates in each ambulacral area and 

 six columns of plates in each interambulaeral area at the mid-zon?. Interambulaeral plates imbricate strongly 

 dorsally and from the center laterally and over the ambulacra. 



Fig. 10. The same specimen (after Meek and Worthen, 1873, Plate 16, fig. 2). Natural size. Outline restored dorsally 

 as conceived by the authors; an interambulaeral plate with secondary tubercles enlarged. 



Lepidesthes carinata sp. nov. Page 424. 



Fig. 11. Keokuk Group, Lower Carboniferous, Crawfordsville, Indiana. Mus. Comp. Zool. Coll., 3,175 (from R. T. J. 

 Coll.), holotype. Natural size. Strongly elevated melon-like ambulacral areas, twelve columns of plates in an 

 ambulacral area and six columns of plates in the interambulaeral areas at the mid-zone as far as ascertained, but 

 the details for most parts are obscure. 



