﻿schuchert] siluric ami devonic cystidea 225 



cerniblc. For detail of this region and the ambulacra, see figure 6, 

 plate xxxvii. 



Anal pyramid small, nol strongl) elevated, composed of 6 pieces, 

 but made quite prominent by the protrusion of the bounding margins 

 of thecal plates 7, 8, 13, and 14. 



Column comparatively stout, and, as is usual in cystids, composed 

 of thick segments near the theca. Length unknown. 



Comparisons. — This beautiful, regular, but small cystid is readily 

 distinguished from the other species of Jaekelocystis by the pyriform 

 outline, strong sculpturing, and the more prominent ambulacra. /. 

 papillatus is also easily identified by the much finer papillose orna- 

 mentation. 



Formation and locality. — A very common species in the quarries 

 and elsewhere near Keyser, West Virginia, many hundred examples 

 having been seen. The first specimen was dug up near Judge 

 Alkire's house by Mr. Frank Hartley of Cumberland, Maryland. It 

 is found associated with Sphcerocystites multifasciatus, S. globularis, 

 and Pseudocrinites gordoni, these four being the common species of 

 the cystid beds of the lower Manlius formation about Keyser. It 

 gives the writer pleasure to name this species for its discoverer, in 

 recognition of his enthusiasm and untiring efforts in the unearthing 

 of many new Siluric and Devonic species of western Maryland. 



Cat. number 35.055, U. S. N. M. 



JAEKELOCYSTIS PAPILLATUS n. sp. 



(Plate XXXVII, figures 9, 10) 



Length of the largest theca 15 mm.; width and depth 12 mm. 

 For general form and sculpturing, see plate xxxvii, figures 9, 10. 



Anal area less prominent than in the other species of this genus, 

 and bounded by plates 7, 8, 13, and only a very small part of 14. 



This species differs from /. hartleyi, to which it is closely related, 

 in the more globular theca, fewer brachioles, absence of grooves along 

 the suture lines of the plates and the papillose sculpturing" of the 

 plates ; also in the fact that the discrete halves of the pectinirhombs 

 are alike and not with one-half buried deeply in a pit with a high 

 rim. Each ambulacrum has from 11 to 12 brachioles on each side, 

 while in /. hartleyi there are 17 in the same length. The pectini- 

 rhombs likewise have more dichopores, there being from 12 to 15 

 in each, while in /. hartleyi there are only about 8. 



Formation and locality. Only two specimens of this species are 

 known from the quarries near Keyser, West Virginia. 



Cat. number 35,057, U. S. N. M. 



