316 PROCEEDINGS OF THE ACADEMY OF [1885. 



Family I.— RETEOCRINIDJE W. & Sp. 

 RETEOCRINUS Bill 



1881. W. & Sp., Rev. II., p. 191. 



L883. W. & Sp.. Amer. Journ. Sci., vol. xxv April), p. 356-268. 

 L884. I'. Herb. Carpenter, Phil. Trans. Royal Boa, Pt. Ill, lsS3, pp. 919- 

 933. 

 Sy/i. Glyptocrinua (in part), Miller; Journ. Cincin. Soc. Nat. Hist. , 



vol. v, April, 1882. 

 Syn. Gaurocrinus Miller (in part). Ibid. vol. vi, December, 1883. 



Reteocrinus is readily distinguished from the other Reteocrin- 

 idae by its well developed underbasals, which extend beyond the 

 limits of the column. From our former list we withdraw Reteo- 

 crinus Baeri, which is a Xenocrinus, and Reteocrinus Richard- 

 soni Wetherby, which we make the t3 T pe of our new genus Can- 

 istrocrin us. 



One more species must be added : 



*188:S. Reteocrinus magnificus (S. A. Miller), Gaurocrinus magnificus, Journ. 

 Cincin. Soc. Nat. Hist., vol. vi. p. 230, PI. 9, fig. 2. — Hudson River gr. — 

 Lebanon, 0. 



CANISTROCRINUS, nov. gen. 

 {jcaviargov, a willow basket ; xpivov, a lily.) 



Syn. Glyptocrinus (in part) S. A. Miller, 1883, Journ. Cincin. Soc. Nat. 



Hist., vol. vi., p. 220. 

 Syn. Udun'riiiUK in part; \Y. A: Sp., Amur. Journ. Sci., vol. xxv, p. 266. 



Generic Diagnosis.. — In general aspect closely resembling 

 Reteocrinus. The radial ridges strong, tube-like; the interradial 

 spaces deeply depressed. Symmetry decidedly bilateral. 



Underbasals perhaps indistinctly developed, more probably 

 altogether absent. Basals five, truncated above for the reception 

 of the lower series of interradials. Primary radials 3X5, of 

 nearly equal size; the lirst and third similar in form. The ridges 

 of the former branching downward toward the basals ; those of 

 the latter upward toward the secondary radials, which they 

 follow until these turn into free ann-plates. Arms branching or 

 simple; composed of single joints, which give off rather strong 

 pinnules. 



Interradial spaces composed of numerous small pieces without 

 definite arrangement. The plates rest upon the basals, separat- 



