INDIANA PALEONTOLOGY. )/8. 



H(»riz(>n: Kaska^kia Limestone. Locality: Big ("lifty, Hardin county. Ky. 

 Collector: ('harles Vt-rv. of New Albany. Ind. Collection of (i. K. Greene. 



The iipecimen. figures 0, 10, 11, also differs somewhat from typical P. 

 chesterensis. the inter-amhulacral spaces forming shallow troughs, thus giving 

 a lobed appearance to the body. In fact, the whole specimen to the distal ends 

 of the ambulacra has a strongly P. (foiJoa'i look and could be easily referred to 

 that species were it not for the protuberant base. 



To the basal plates, the body is sub-ellipsoidal, instead of conical in P. 

 chesieronsis. The deltoids are more than a third as long as the ambulacra, but 

 do not project above the ventral surface. The ambulacra are nearly tlat. mod- 

 erately wide and but little sunken beneath the bounding radial lips. 



The openings on the ventral side are medium in size. 



Surface ornamentation unknown. 



Horizon: Kaskaskia Limestone. Locality: five miles northwest of Bowling 

 Green. Ky. Collection of G. K. Gretnie. 



PP:NTREMITES robust us. Lvou. Rowlev. 



Plate 30. Fio. 12. 



Our specimen differs little from Lyon's type, except in size. The basal 

 plates form a low conical cup and the line from the top of the basal cup to the 

 distal end of the ambulacrum is a little oblique. The inter-ambulacral spaces 

 form troughs and so throw the. ambulacra into lobes. The fork pieces are 

 hardly more than half the body length while the deltoids are more than a third 

 the ambulaeral length, but do not extend upward to the spiracles. The ambu- 

 lacra are rather wide, alm(»st Hat. and but little below the bounding edges of the 

 radials and deltoids. Here again we have a specimen strongly like /-*. goiloni 

 above the ambulaeral entls. 



From the Kaskaskia Limf>tone of Newman's Ridge. East Tennessee. Col- 

 lection of G. K. Greene. 



The various species of riie genius Pentremites may be referred to a few 

 simple grfiups of closely related forms, P. r/icstf/rinsi-s, P. rohai^tus P. fiemi- 

 spher'trus falling in naturally witli P. gorloni, while P. .■s>///i//n'f/-t'r>f.y!. P. ele- 

 gans, P. rolgr'inn.s. and perhaps /-*. fJardtn.s, range themselves witli /-*. pi/rl- 

 foi'uits. 



The siiJrntus group would inchRle P. nht .\)is, P. '-/n roki >i.s. J*. KuJraftis^ 

 P. angularis, P. spntos'/s, P. hiuKKJInail'i and P. hasilar/.-^. P. I'onoideus^ 

 P. koninekanus and P. henvili^-t' would form a group of kindred species. 



Penti'einites burlt'/igto/ie/isis and /-*. eloagatuH have affinities with both 

 the godon'i and conoideux groups. 



