1879.] NATURAL SCIENCES OF PHILADELPHIA. 271 



radials. Anal plates resting upon the truncated upper side of the 

 larger basal, or sometimes placed independently in line with second 

 and third radials. They consist of a series of from two to five 

 narrow quadrangular plates, longitudinally arranged, the upper 

 ones forming the dorsal side of a small lateral proboscis. Column 

 comparatively large, rapidly tapering, composed near the body of 

 thin joints, which gradually increase in thickness as they diminish 

 in diameter. Central perforation of medium size, pentangular as 

 far as observed. 



Geological and Geographical Distribution. Taxocrinus, so far 

 as known, appears first in Europe, where it is represented in the 

 Upper Silurian by 2 species, in the Devonian by 3, and in the 

 Subcarboniferous by 2. In the United States and Canada (if we 

 exclude Lecanocr.(?) elegans, from the Trenton group), it is first 

 found in the Devonian, from which 4 species are known, and from 

 the Subcarboniferous 13 are described. 



We include in the typical form of the genus the following spe- 

 cies : 



1856. Taxocrinus affinis Miiller. Neue Echinod. d. Eifel, p. 244, pi. 1, figs 1, 2 ; 

 also Schultze, 1866, Echinod. Eifl. Kalk., p. 34, pi. 4, fig. 2. Devonian. 



Eifel, Germ. 

 1843. Taxocr. brevidactylus Aust. (Cladocrinus brevidactylus). Ann. and Mag. 



Nat. Hist., vol. ii , p. 198; also Rec and Foss. Crin., p. 89, pi. 11, fig. 4. 



Subcarbon, Ireland. 

 * 1863. Taxocr. communis Hall. (Forbesiocr. communis). 17th Regts. Report. N. 



Y. State Cab., p. 55 ; also 1877, Paleont. Rep. Ohio. Vol. ii. p. 169, pi. 



12. figs. 3-5. Waverly group. Richfield, 0. 

 1836. Taxocr. Egertoni Phillips (Poteriocr. Egertoni). Geol. Yorksh., ii. pi. 3, 



fig. 39. Subcarbon. Yorkshire, Eng. 

 *1858. Taxocrinus Giddingei Hall. (Forbesiocrinus Giddingei). Geol. Rep. 



Iowa, vol. i. pt. ii. p. 633, pi. 17, figs. 2, 4. Keokuk liinest. Illinois, 



Iowa. 

 1865. Taxocr. gracilis Meek and Worthen. Proceed. Acad. Nat. Sci. Phila., p. 



142 | also Geol. Rep. Illinois, vol. iii. p. 421, pi. 13, fig. 3. Hamilton gr. 



Jackson Co., 111. (not Taxocr. gracilis Schultze = Rhopalocrinus gracilis, 



Wach?m. and Spr. 

 *1867. Taxocr. incurvus Trautschold. (Forbesiocr. incurvus.) Crin. des jiinge- 



ren Bergk. Moskau, p. 31 ; also Kalkbr. von Mjatschkowa, p. 126, pi. 14, 



fig. 11, and pi. 15, fig. 3. Subcarb., near Moscow, Russ. 

 1858. Taxocr. interscapularis Hall. Geol. Rep., Iowa, vol. i., pt. ii., p. 482, pi. 



1, fig. 3. Hamilton gr. New Buffalo, Iowa. 

 1867. Taxocrinus juglandiformis Schultze. Echinod. Eifl. Kalkes, p. 35, pi. 4, fig. 



4. Devonian. Eifel, Germ. 



