672 



SILURIAN ENCRINITES. 



base of the arms is separated from the scapula by one curved joint, as in Cyathocrinites quin- 

 quangularis, and C. planus of Miller. 



It appears to me that, hereafter, these three species will not be ranked in the same genus 

 with Cyathocrinites rugosus of Miller. 

 Cyathocrinites piriformis, n. s. Phil. PI. l'J. f. 6. 



Its analogy to C. tuberculatus is considerable; but in Miller's technical arrangement it 

 ought probably to constitute a new genus. The great width, general equality and lateral union 

 of the plates, till the arm divisions amount to twenty, constitute easy characters. The surface 

 is marked with a faint irregular ornament not unlike Cyath. tuberculatus. The upper co- 

 lumnar joints are very thin. 

 Cyathocrinites rugosus, Miller, p. 89. PI. 18. f. ]. 

 Marsupiocrinites (Phil.). 

 Marsupiocrinites ccelatus, Phil. PI. 18. f. 3. 1 



Pelvic plates unknown, (probably five) ; scapulo-costals five, wide, hexagonal, each exca- 

 vated on the upper edge to receive a series of small wrinkled plates, finally terminating in four 

 longitudinally sutured fingers. The bases of the arms are separated by five interscapular plates. 

 The whole surface is crenulato-striate ; the striae assuming a radiated form on the scapular and 

 interscapular plates. 



The column (seen in part) appears to have been pentagonal. The twenty fingers com- 

 posed of two rows of joints (whence the apparent longitudinal suture) had perhaps no lateral 

 tentacula ? 

 Hypanthocrinites (Phil.). 

 Hypanthocrinites decorus, Phil. PI. 17. f. 3. 2 



In this new genus the lowest plates clearly seen appear to correspond to the first costals 

 of the genus Actinocrinites \ the pelvic plates were probably small. 



First costals (F) five, tumid, hexagonal, equal and similar, supporting five second costals 

 (F'), and five truncato-cuneiform scapulae (H). On the two lateral superior edges of the 

 scapulae rest two pentagonal arm-joints, each bearing a cuneiform hand-joint, which supports 

 two longitudinally sutured fingers. The summit of the scapula bears a conical plate which 

 divides the arms and fingers of each pair. 



Between the five radiating costal rows are five large tumid diagonal intercostal plates (G). 

 On these rest in part the arm-joints, and between them two other approximate plates some- 

 what conical in form, which divide the pairs of arms and fingers, and unite with long ribs 

 which terminate near the mouth in large tubercular plates. Similar ribs are attached to the 

 single conical plates which surmount each scapula. Thus the proboscis (probably contractile) 

 which rises above the short plumose fingers, is surrounded with several rows of tubercles, the 

 lower one being formed of ten. 



The five large intercostals surrounding by their ten bordering plates (3 a.), ornament the 

 basis of this encrinite with five floriform disks of great regularity and beauty. The large 



1 Believed to be a new genus, with analogies to Rhodocrinites of Miller, and Actinocrinites tesseracondactylus 

 of Goldfuss. The name is taken from fxapaviros, a purse or bag. 



2 The name of this new genus is taken from the floriform aspect of the basal portion of the body, (bird, under ; 

 ixvdos, a flower.) 



