PLATE 28. 



Pholidechinus brauni sp. nov. Page 299. 



Kit;*- 1-9. Keokuk Group, Lower Carboniferous, Crawfordsville, Montgomery County, Indiana. 



Fig. 1. F. Uraun Coll. Paratype. X 2.1. Ambulacra narrow throughout, plates laterally meeting the interanibuHtrra 

 or alternate plates in part nearly or quite cut off from interambulacral contact. Pore-pairs slightly biserial. Inter- 

 iunbulacra with nine columns in each area. The primordial interambulacral plate is in the basicoronal row in area I, 

 and is restored in area A. Interambulacral plates imbricating strongly dorsally and laterally and rounded upward 

 and toward the ambulacrum on either side, except the median column, which is rounded and imbricates laterally 

 in two directions (compare text-fig. 32, p. 75). Teeth in place, ambulacral plates only on the peristome. Same 

 specimen as photograph, Plate 27, fig. 2. 



Fig. 2. Mus. Comp. Zotil. Coll., 3,109 (from R. T. J. Coll.), holotype. X 2.1. Ambulacral plates ventrallyare all pri- 

 maries, meeting the interambulacrum equally. Ten columns of plates in interambulacrum C, the last column origi- 

 nating late. The beveled edges of the plates show clearly below, the initial plate of column 8. There are flanges on 

 the outer and dorsal border of each plate, compare fig. 9. Spines and tubercles in place. Same specimen as photo- 

 graph, Plate 27, fig. 1. 



Fig. 3. Same specimen as fig. 2, showing the details of tubercles and spines from the area marked X, in fig. 2. X 8. 



Fig. 4. British Mus. Coll., E 10,678 (from R. T. J. Coll.). paratype. X 2.1. Ten columns of plates in interambulacrum 

 A and apparently in I, the tenth column originating earlier than in fig. 2. Column 9 in both areas imbricates dor- 

 sally and laterally in two directions; columns 7 and 8 in area A drop out passing dorsally. Same specimen as 

 photograph, Plate 27, fig. 3. 



Fig. 5. Same specimen as fig. 4, from the area marked X in that figure, showing alternate plates nearly or quite cut off 

 from the interambulacrum. Pore-pairs in peripodia. X 5.4. 



Fig. 0. Same specimen as fig. 4, from the area marked XX in that figure, showing alternate plates narrowed but not cut 

 off from the interambulacrum. X 5.4. 



Fig. 7. Amer. Mus. Nat. Hist. Coll., "- 2 1 4 -, paratype. X 2.5. In profile to show the lateral beveling; adradial plates 

 are shaded. 



Fig. 8. The same specimen. X 2.5. Shows ambulacral plates alt ornately meeting and cut off from interambulacral 

 contact; biserial pore-pairs and beveling of plates. 



Fig. 9. Same specimen as photograph, Plate 27, fig. 1, and this Plate, fig. 2. Holotype. X 3.2. Plates from near the 

 mid-zone of area A, showing delicate attenuated flanges that exist superficially on the dorsal and both sides of column 

 9, and on the dorsal and lateral border of the plates of other interambulacral columns, a unique specific character 

 as far as known. 



Fig. 10. Keokuk Group, Montgomery County, Indiana. Mus. Comp. Zool. Coll., 3,111 (from R. T. J. Coll.), paratype. 

 X 2.2. Dorsal portion of a test showing two low, wide genitals each with numerous genital pores. 



