E. IMPERIALIS. — SPICULATION. 77 



were decidedly rare in the parietal ledges. The principals are 

 exce.-sively short, being represented by a knob-like swelling 

 separated from the central node by a narrow constriction. 

 They are quite unlike those in E. regcdis, in which, according to 

 F. E. Schulze's representation, they should be short but narrow. 

 The strongly divergent terminals, 3-5 to each principal, are 

 smooth, nearly straight and of moderate length. 



The graphiocomes measure up to 330/.« in diameter. They 

 are tolerably common everywhere in the periphery of the wall, 

 though it may be comparatively rare to meet with one in a 

 perfectly intact state. The sheaves of terminals may be 154/^ 

 long and 20/'- broad. Detached and isolated terminals — i. e., the 

 rhaphides — are scattered here and there in the superficial region, 

 lying irregularly but mostly more or less vertically to the surface 

 along with the hilt- rays of the dermal ia. In comparison wdth 

 E. marshalli, the rhaphides so situated are not so numerous. 

 The central remnant of the rosette after completely shedding off 

 the rhaphidial terminals, has been very frequently met with. 

 The discs at the end of principals are then seen studded all 

 over their external surface with small prickles. Different stages 

 of the srowth of the terminal sheaf have also been found. The 

 rhaphides composing each sheaf are at first very short and ex- 

 ceedingly fine (fig. 13). For further account of their develop- 

 ment, see under E. marshalli. 



In E. regalis, which clearly is very nearly related to the 

 present species or to E. aspergillum, F. E. Schulze has entirely 

 missed the graphiocome; nor does he appear to have seen any 

 free rhaphides. Nevertheless, I consider it not altogether im- 



