68 The Ohio Journal of Science [Vol. XXI, No. 2, 



A comparative study of the type of Crinocystites chrysalis, of the 

 Chicago University specimen of that species, and of Eucalyptocrinus 

 proboscidian s demonstrates that Crinocystites chrysalis is a cast 

 of the interior of the anal tube of a species of Eucalyptocrinus, using 

 that term in the broad sense in which it is applied at present. The 

 following is a description of the Chicago University specimen. 



Chicago University specimen. — The specimen retains distinct impres- 

 sions of the exterior surface of the upper part of the 10 wing-like processes 

 that surround the tegmen, and that serve as partitions between the 

 vertical compartments sheltering the arms. No trace of these arms 

 remains. The upper edge of these processes projects horizontally out- 

 ward, their total extension across the entire width of the specimen being 

 IS mm., while 7 mm. farther down the attenuated upper part of the teg- 

 men has a width of only 5 or 6 mm. The upper surface of the wing-like 

 processes forms a platform, above which rises a further extension of the 

 tegmen in the form of an anal tube. At its base this anal tube has a 

 width of 7.5 mm., decreasing to about 3.5 mm. in a length of 14 mm., 

 above which it is not preserved. The plates forming the anal tube are 

 elevated towards their centers in a strongly nodose manner. They are 

 arranged in about ten vertical series, the lower plate of each series being 

 directly above the top of one of the wing-like processes already described. 

 Four or five plates occur in each vertical series, as far as preserved, the 

 plates in adjoining rows alternating with each other. Counted in a 

 transverse direction, the plates at the base are arranged in circles of five 

 plates each, the plates of successive circles alternating. It is not known 

 whether the number of plates in a circle continues to be five as far as 

 the top of the anal tube. 



The cast of the interior of the anal tube is continued downward into 

 the cast of the interior of that part of the tegmen which is included 

 between the top of the wing-like processes. The upper part of this cast 

 of the interior, for a length of 14 mm., retains traces of the plates 

 forming the anal tube; the lower part, G mm. in length, shows a vertically 

 elongated flattened area beneath each of the vertical rows of the anal 

 tube, somewhat as in Eucalyptocrinus proboscidialis. In the latter, 

 however, that part of the tegmen which is included between the upper 

 part of the wing-like processes is constricted strongly beneath while in 

 Crinocystites chrysalis the corresponding part is constricted only suf- 

 ficiently to give the entire cast included under that name by Hall an 

 inverted clavate appearance, with the maximum expansion on a level 

 with the top of the wing-like processes. 



The Chicago University sjjecimen agrees with the type of Crino- 

 cystites chrysalis in having the anal tube moderately curved lengthwise. 

 That part of the cast of the exterior of the anal tube of the Chicago 

 University specimen which is best preserved belongs to the concavely 

 curved side of this tube, but the amount of this curvature is slight. 

 That part of the cast of the interior of the anal tube which is best pre- 

 served belongs to convexly curved side of the tube. This curvature is 

 more distinct, and this is the side of the tube here figured. 



