﻿248 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 47 



Dr. B. E. Walker, of Toronto, Canada, has presented to the 

 National Museum a very well-preserved specimen of C. subglobosits, 

 which differs from all others in shape and in the number of plates. 

 It is more globose, higher, and somewhat more drawn out posteriorly. 

 The anal tube also protrudes more than is usual. This specimen, 

 instead of having 25 plates, the normal number, has 29, as shown in 

 the following diagram. An analysis based on normal specimens leads 



Fig. 37. — Analysis of an abnormal specimen of Ccclocystis subglobosits (Hall). 



to the conclusion that plates 15, 16, 18, and 21 are divided, thus 

 producing the 4 additional plates. It seems rather odd that division 

 in these plates takes place so irregularly ; 2 of the plates bear pectini- 

 rhombs, one being a simple thecal plate, and the other a deltoid. 

 The only species of this genus is C. subglobosits (Hall). 



CCELOCYSTIS SUBGLOBOSUS (Hall) 



Hemico smites subglobosits Hall, Twentieth Rep. N. Y. State Calx Nat. 



Hist., rev. eel., 1S68 [1870], p. 359, pi. 12, fig. 13. 

 Sphcerocystites dolomiticus Jaekel, Stammesgeschichte der Pelmatozoen, 



Berlin, 1, 1899, p. 289, fig. 63. 

 Ccclocystis subglobosus Schuchert, Amer. Geol., xxxn, 1903, p. 235. 



Rare in the Niagaran limestone about Chicago, Illinois. See 

 text-figures 36 and 37 for the analysis of two specimens of this 

 species. 



Cat. numbers 35,061 and 35,155, U. S. N. M. 



Sphcerocystites Hall 

 Sphcerocystites Hall, Amer. Jour. Sci. (2), xxv, 1858, p. 279.— Hall, 

 Nat. Hist. N. Y., Pal., in, 1859, p. 130.— Schuchert, Amer. Geol., 

 xxxn, 1903, p. 232. 

 Sphcerocystis Haeckel, Die Amphorideen und Cystoideen, Beitr. Morph. 

 u. Phyl. d. Echinodermen, Leipzig, 1896, p. 133.— Bather, Treatise on 

 Zoology, hi, Echinoderma, London, 1900, p. 63. 

 Original definition. — "Body spheroidal, wider than high. Arms 

 in two principal pairs, with numerous bifurcations. Brachial sulci 

 obliquely lobed. Mouth longitudinal ? apical: anus [=madre- 

 porite] subapical: ovarian [— anus] opening upon the summit. 



