105 



CHAPTER v.* 

 PALAEOZOIC ECHINODERMATA. 



Crinoidea. (Articulata.) 



Cupressocrinus (Gold . ) . 



It will be observed in the following descriptions of two species 

 of this genus hitherto only known in the foreign Devonian strata, 

 that I have attributed interscapular plates to its cup as in Pote- 

 riocrinus, although such are not indicated in the figures or ge- 

 neric characters of Goldfuss. I have however detected them in 

 an authentic specimen of his C. crassus from the Eifel in the 

 Cambridge collection, although not so clearly as in the following 

 species. In the number and position of the plates of the body, 

 Cupressocrinus and Poteriocrinus are identical; and in both, 

 the articulations for the arms extend the entire width of the 

 upper edge of each of the scapulse ; but there is a striking dif- 

 ference in their form, which seems dependent on the total dis- 

 similarity of their arms ; the cup in the latter genus is elongate- 

 conic, the comparatively narrow scapulse giving off arms of mo- 

 derate width, dichotomizing frequently, while in Cupressocrinus 

 the cup is of an extremely wide saucer-like form, and the scapulse 

 of inordinate width to give origin to the curiously wide, massive, 

 simple arms which render the genus so remarkable. 



Cupressocrinus calyx (M'Coy). 



Sp. Char. Cup very wide, evenly convex, saucer-shaped, three 

 times wider than long ; pelvis small, slightly concave, penta- 

 gonal, of five pentagonal pieces ; alternating with and above 

 which are five large first-costals, their length and width equal 

 to the diameter of pelvis, four pentagonal and one with a very 

 short sixth side ; alternating with, and above those, are five 

 pentagonal scapulse, as long as the costals, but the width 

 double the length ; to the short side of the hexagonal costal is 

 obliquely attached a long pentagonal intercostal supporting 

 two very small interscapular plates; scapulce very thick, 



* Tlie new species described iti this chapter date from the 'Annals of 

 Natural History ' for April 1849. 



