Dec, 1920] 



Cvstids and Blastoids 



37 



Wellerocystis kimmswickensis Sp. nov. 

 (Plate I, Figs. 12 A, B.) 



Theca 20 mm. in height and 15 mm. in width, ovoid in form, with 

 attachment area for column about 4 mm. from the vertical axis, on the 

 side opposite to that occupied by the anal opening. Oral aperture at the 

 summit of the theca, a millimeter long in a direction parallel to the 

 proximal part of the main food-grooves, and about a quarter of a milli- 

 meter in width, the elongation being in a direction almost at right angles 

 to a vertical plane passing through both the anal opening and the 

 attachment area for the column. That one of the two primary rays 





Fig 



Diagram showing the arrangement of the plates in 

 Wellerocystis kimmswickensis . 



The outlines of the plates in the apical region, between the rays, are very 

 iincertain, but are indicated as well as they can be ascertained by means of dotted 

 lines. The position of the anal aperture is at A. The three recumbent rays are 

 numbered I, II and V. The food-grooves follow those sides of the rays which are 

 marked by two closely placed parallel lines. The oral aperture is represented in the 

 diagram by a circle at the upper end of ray V. The food-groove extending from the 

 oral aperture toward the left connects with rays I and II. There are 3 basal plates, 

 indicated by parts of a circle at their bases, the latter limiting the areas of artic- 

 ulation of these basal plates with the column. 



which encircles the anal aperture remains unbranched and is only 

 10 mm. in length, measuring along its convexly curved side. The other 

 primary ray, on the opposite side of the oral aperture, is IS mm. in 

 length; about 2.5 mm. from this aperture a branch of intermediate 

 length is added on the left side of this second ray, thus forming a total 

 of three rays. The number of brachioles supported by the ray encircling 

 the anal aperture was about 5; the number on the other primary ray 

 equalled about 7 or 8, and that on the branch of this second ray was about 

 10. Viewed directly from above, the food-grooves with their branches 

 leading to the facets formerly supporting the brachioles resemble those 



