92 The Ottawa Naturalist. [November 



Geo. Surv. Canada, Dec. 3, 1858, p. 61, pi. 5, figs. 

 1-lb, 2-2b. 

 Figure 1 (No. 1391g, in Victoria Memorial 

 Museum) represents the right side of the theca; 

 o is the anal pyramid. In figure lb, the smooth 

 proximal parts of the polygonal plates surround- 

 ing the anal pyramid are represented incorrectly 

 as though forming a circle of separate plates 

 surrounding the anal pyramid. In figures la and 

 2a, the non-porous epistereom has been removed 

 by weathering from the marginal parts of the 

 thecal plates. Figure 2 (No. 1391, in Victoria 

 Memorial Museum) presents a view of the 

 anterior side of the theca, with the anal opening 

 on the left upper margin of the figure; the nodular 

 stereom mass supporting the right pair of arms is 

 seen immediately below the number 2, and the 

 angle at the upper right hand margin of the figure 

 indicates the location of the other stereom mass. 

 Figure 2b is a very unsatisfactory representation 

 of the transverse food-groove extending from the 

 central mouth in opposite directions to the base 

 of the stereom mass, where it forks dichotomously 

 at each end. 



Grant, Trans. Ottawa Field-Nat. Club, 1, 1880, pi. 1, 

 figs. 1-5. 

 Figure 1 (No. 333 in Victoria Memorial Museum) 

 probably presents a view of the anterior side of 

 the theca, in addition to a view of the entire 

 length of the column, including its base. Only 

 the lower parts of the arms and pinnules of this 

 specimen are represented in this figure. The 

 remaining figures are re-publications of figures in 

 Decade III, of Billings, figs. 2, 3, 4 and 5 cor- 

 responding to figs. 1, 2, lb and 2b respectively of 

 the Decade 



Chapman, Exposition of the Minerals and Geology of 



Canada, 1864, p. 109. 

 Haeckel, Amphorideen u. Cystoideen, 1896, p. 70, pi. 

 1, figs. 4-4c. 



Figure 4 is a reproduction of Billing's figure 1 on 

 plate 5 of Decade III, amplified by Haeckel so as 

 to suggest the appearance of a complete arm 

 system and a complete column. The biserial 



