464 NEW YORK STATE MUSEUM 



unpublished, which were found with the manuscript and have added our 

 own observations as well as a number of figures, explanatory of the latter 

 [see pi. 31]. 



Dr Gurley has given the following description : 



The polypary in this species is parallel-sided blunt-fusiform, and con- 

 sists of skeleton and periderm. The skeleton shows, at and imbedded in its 

 base a body apparently a sicula, flanked on either side by a spine which is 

 directed obliquely upward. Two virgulas are present, each zigzagged in the 

 basal expanding portion of the polypary, straight in the middle (parallel- 

 sided) portion, and (?) again zigzagged in the upper contracting part. From 

 the convex angles of the zigzagged, and at intervals from the straight portion 

 of the virgula, a parietal ledge ' runs in each lateral wall to the ventral mar- 

 gin, where it undergoes an abrupt deflection downward to the parietal ledge 

 of the theca next below, to which it appears to connect just before (i. e., at 

 a point on the lateral surface just within the ventral margin) that ledge 

 reaches its point of downward deflection. At the latter point a mouth ledge 

 connects the parietal ledge with its fellow on the opposite side. These 

 three chitinous threads (the horizontal limb of the parietal ledge, the ver- 

 tical limb of the same and the mouth ledge), all meet at the point of 

 deflection with rounded edges, and together form the rim of the mouth 

 opening, which is thus somewhat squarish or slightly trapezoidal. I have 

 seen nothing corresponding to the inner cross-ledges and the material fur- 

 nishes no data for an opinion pro or con as to the existence of any interthecal 

 partition planes. 



The periderm consists of three, rarely only two, longitudinal series of 

 meshes of a subrhomboidal shape which alternate in adjacent rows, and give 

 off from the middle points of t-he meshes of the outer rows (the rows along 

 the ventral margin) short, stout spines which arc the mouth ledges crushed 

 V -shape. The relation of the three rows of peridernial meshes to the skel- 

 eton is not known. The parietal ledges form the upper and lower borders 

 of the meshes, and are deflected inwards (i. e., into the intra-polyparial 

 space) to their virgular connection at the inner borders of the outer rows of 

 meshes (?). The meshes are covered by a membrane which is markedly 

 thinner in the center of the mesh. 



The form of the rhabdosomc and the relation of the three rows of peri- 

 dermal meshes to the skeleton alluded to above is made clear by plate 31, 

 figure 11. The lateral faces were flat and fullv covered by the continuous 



1 L here follow the nomenclature of Holm [Bihang til kongl. Sv. W-t.-Ak.nl. II. null. 

 1890, XVI, no. 7]. 



