FOSSIL INVERTEBRATED ANIMALS. 513 



supported. They are divided into five parts. Each of these 

 parts is covered with transverse and very regular striae, cut in 

 their middle by a longitudinal line, a little sunken, and which 

 proceeds from the summit. These regular bodies are changed 

 into a kind of chalcedony. There is reason to believe that the 

 head had the faculty of opening like that of the other encrini. 



The ancient strata of Ranville, near Caen, present very 

 singular cylindrical bodies, to which, in Germany, the name 

 of astropodes have been given, and sometimes that of scyphoids. 

 These bodies, changed into calcareous spath, and composed of 

 slices applied one above the other, are pierced in the direction 

 of iheir axis. They have some relations with the encrini, by 

 their division into five parts ; but they differ from them in other 

 respects. Their form is greatly varied: some have that of a 

 vase ; others that of a tun, or little cask. Their sizes vary 

 from that of a middling hen's-egg to that of a small nut. In 

 some the base is concave, and covered with striae, radiating 

 from the centre to the circumference. On the edge of the 

 upper part are five small elevations, on each side of which are 

 seen two small indentations, which must have carried other 

 pieces not now found there. The inside of this body is concave 

 as far as the base ; others have the upper part a httle convex, 

 and covered with radiating striae. On this kind of platform are 

 seen five carinae, star-wise ; and between each of them is a cleft, 

 which extends from the centre to the circumference. There 

 are some of these bodies, however, in which these apertures are 

 not seen. 



Another species, or variety, very remarkable, which has the 

 form of a vase, and to which M. de France has given the name 

 of astropodium elegans, has, on the edges of its upper part, five 

 indentations, or sinkings, agreeably striated, which may be 

 compared to the external impressions left by five bivalve shells, 

 covered with striae, proceeding from the summits. This upper 

 part is almost fourteen lines in diameter, and has a hole in the 

 centre. It is very probable that the indentations served to 



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