Species of tiik Ciikmuno Group. 113 



from the surface of the vase with a stout body which, at some little distance 

 above that sui-face, is divided by a vertical and a horizontal gro<jve, usually of 

 unequal depth. These grooves make a division of the surface into four lobes 

 of irregular form and distinctly pendulous ; upon the lowest horizontal row 

 the two lobes of the inferior division of the node are very long and confluent 

 for a considerable distance, producing digitiform pouches. Those of the 

 median rows appear to be somewhat less elongated, but all have a downward 

 direction. There are some irregularities in the division of the nodes. In one 

 instance the horizontal groove is wanting, leaving but two nodes on the lol)e ; 

 in another; one of the four lobes appears to be divided into three, and the other 

 into two parts. The uppermost, or apertural, series of nodes differs from the 

 rest in having the lobes short and ari'anged singly or in simple pairs which 

 seem not to correspond invai-iably in position with the vertical rows in which 

 the lower nodes are arranged. The growth of the nodes in this row was, 

 however, quite irregular ; they are short, and while in some specimens they 

 are erect and in others inclined downward, their normal position was probably 

 directly outward. No specimen is sufficiently perfect to indicate precisely the 

 number of nodes in this row. 



A slight variation from the type of structure described is indicated by one 

 example which shows a coalescence of, or an indistinctness between the first 

 and second horizontal rows of nodes at their base and also a partial loss of the 

 quadrilobed surface of the second row. Each specimen, however, presents its 

 peculiar modifications in the number and form of the nodes and lobes. 



Retwulum. Over the pedicel the spicular bands are extremely fine, but 

 the reticulation is distinct. Toward the base of the cup the longitudinal 

 bands become prominent while the horizontal bands are obscured. On 

 the vase, the net-work is fine in comparison with that of Hyonocekas, and 

 the obscurely subprismatic form prevailing in that genus is here totally lost. 

 The quadrules of the most prominent series measure about 2 mm. on each 

 side, and these are crossed by one or two finer series. Over the lobes the 

 spicular bands all spread apart as in Hydnoceras. There is no satisfactory 

 evidence of spicular tufts at the extremities of the nodes, though presumably 

 such tufts existed ; nor are there other spicular expansions except fine, narrow, 

 longitudinal laminae following the courses of the larger spicular bands. 



Toward the base of the cup there seems to have been a thickening of the 

 spicular strands which on the inner or gastral side of the sponge apparently 

 converged to an apex near the union of the cup with the pedicel. This inter 

 ual convergence is exhibited in several instances where the sponge has been 



