[DAW80N] FOSSIL SPONGES AND OTHER ORGANIC REMAINS 117 



Many fragments of this species liave been found from time to time 

 showing long stoul tapering anchor! ng-rods with masses of \on<r slender 

 simple spicules near them ; but in 18!»5 for the first time nearly perfect 

 specimens were observed. They consist of discs somewhat larger than 

 those of S. sancta, made up of fine straight spicules radiating from a ])oint 

 near one side and rather coai-ser than those of S. sancta, and showing, 

 hero and there a tendency to be aggregated more densely as if in bundles 

 but this is not very inarked. At and toward the circumference there are 

 occasionally a iew very small cruciform spicules which, as they are not 

 confined to one specimen, I regard as probably the remains of an outer 

 or cortical layer. If they are accidental they must be the smaller spicules 

 of disintegrated ProtospongiR' entangled in the spicular surface of Ste- 

 phanella. It seems more likely, liowevcr, that thev are a part of its 

 structure, in which case it furnishes an example of a sponge with a dense 

 internal skeleton of radiating spicules. Fig. 27 represents a nearly 



iS;k^ 



Fm. 28.—Stephanella Hindii. FraRment 

 with anchoring-rods. 



Fig. W.Sfepfianella ? Anchoring- 

 rods and part of the spicules, enlarged. 



complete specimen, and Figs. 28 and 29 disintegrated fragments with the 

 anchoring-roots, which in some specimens are longer and more taperino- 

 than in others, though always very stout at the base. * 



In Dr. Ami's specimens from Ottawa, a few stout anchoring-rods 

 and cruciform spicules are found in the same ^labs with Stephanella but 

 none of them are seen to be attached. I think it not improbable, how- 

 ever, that the former, at least, belong to Stephanella. 



