2-i6 Systematic Paleontology 



meet each other at the siTture lines of the j^hitep of which they are a part, 

 but are restricted to the prominent pits. From 40 to 45 grooves in each 

 pit. Anal pyramid depressed, composed of 6 pieces and surrounded by a 

 ring of 3 large aboral and 7 small oral pieces. Hydropore minute, closed 

 by a pyramid of 4 pieces, and situated immediately in front of the large 

 niadreporite occupying the greater portion of plate 18. 



Fig. 14.^ — Diagrams showing the manner and number of ambulacral branches in 

 a young, adult, and old specimen of Splicer ocystites multifasciatus Hall. 



Column slender, with about 16 stout and equally large segments be- 

 neath the theca, followed by others of unequal size of which the larger seg- 

 ments are widely separated. Length of one of the largest theca 19 mm.; 

 transverse diameter in both directions 24 mm. Another large theca has a 

 length of 19 mm. ; diameter in the direction of the tAVO upper pectinirhombs 



23 





Fig. 15. — Analysis of Spharocystites multifasciatus Hall. 



20 mm., and in the opposite direction through the anus 22 mm. A greatly 

 depressed specimen has a length of 13 mm., and a diameter of 20 mm. A 

 young theca has a length and diameter of 9 mm. Base of theca more or 

 less excavated, greatest in the depressed specimens. Plate 12 rests on 

 basal plate 2. 



Occurrence. — ^Helderberg Formation, Keyser Member. Keyser, 

 West Virginia. Abundant. Cumberland, Maryland. 



Collection. — Maryland Geological Survey. 



