Canadian Record of Science. 



slab of shale; their spicules have been loplaced by pyrites 

 precinely the same as in the Metis Hpeci mens. The sponges 

 were evidently vusiform, gi-adually increasing in width 

 from the base upward, their summits have not been pre- 

 served, but with a length of 65 mm. thoy are 40 and 30 

 mm. in width, respectively. Owing to compression, the 

 opposite walls are now nearly in contact, being only separ- 

 ated by a mere Him of the shaly matrix, hardly half a 

 millimetre in thickness. The shale has split in such a man- 

 ner as to expose in some places the outer surface of the 

 wall, and in others, the inner surface of the opposite wall. 



The wall is very delicate, and consists of quadrate or ob- 

 long areas formed by slender longitudinal and transverse 

 strimds or fibers, of which the former aie the more prom- 

 inent. As in Protospongia, the quadrate areas are formed 

 by the four transverse rays of cruciform, or five rayed spic- 

 ules, but these are disposed so that their j-ays overlap each 

 other, and thus form fascicles of closely opposed pai-ailel 

 rays. The spicules in the transverse strands of the wall are 

 less thickly grouped together, and even in some of the 

 larger squares they may be arranged singly, whilst the 

 smaller squares are generally bounded by single spicules 

 only. The longitudinal strands principally consist of 

 cruciform (?) spicules, but it is possible that elongated 

 filiform spicules may likewise be present. There are plain 

 indications of a fifth or distal ray in many of the principal 

 spicules of the wall, shown by a very minute knob or blunt- 

 ed process projecting from the central node of the trans- 

 verse rays, which may represent a partially developed v&y 

 or the broken stump of a complete one. In some places, 

 also, there is a continuous film of pyrites, piobably indicat- 

 ing a membrane of very minute spicules or an agglomera- 

 tion of flesh-spicules, now replaced by this mineral. 



The basal portion of these specimens is incomplete, but 

 there are indications of an extension of the longitudinal 

 strands of the wall downward into the a tuft of anchoring 

 spicules. 



This genus is mainly distinguished from protospongia by 

 the fascicular arrangement of the spicular rays in the prin- 



i 



