fjfimd^o, Id/c^. 



230 



THK PANAniAN NATrRAMST. 



\yo\. Tli. 



ON SOMK NEW ()U TJTTM: KNOWN FOSSILS 

 F1U).M TllK SI UK I AN AND DKV<jNIAN ROCKS 

 OF ONTAUIO. 



S I L U II I A N . 



;^^^ 





Fir. 1. — Auloco) li„i Gr-nii>. — A ii.nrly pfrfcit s|n(iiinn. 

 " '2. — Tlif wiiii:iitit 1)1 ;i luij<:'r 8|i'iiiii, n. 1 



(I'olli (lifiiivs natiinil sizo. Tin- trui- . iiiu.u tcis ^^{ ilic snrliice 

 I'HMiiot l>i' j)i'!-fc( ily rf|>tfsrht«'<l \)\ xvuoil ciiuiMviiii'-.^ 



(lonuM Art.'iconNA iN.(i,) 



111 a }»ox of iossil^ lati'ly sent t'> tho (jiMiloirioal Survey bv 

 Major < 1 1, lilt, iif li:iniiltnii, there iire sereril s|i(.'('iineii» which 

 nppoar lo ni • to liolon'^ to ;j now «r<»mi'« ot" S|ioiit;os. The most 

 porlpct U of an I'lniiuritc. ovato. or jivriforni >li iju*. Tlie hirsror, 

 or uppor (*xtr>'iiiity, i' more or less comimvo. with a small circular 

 i^pui-o in the centre, which appears to be the mouth of a tubular 

 cavity tluit peiu'tr.ite<l inwinls ami ihnviiwanlH, Mioni^ the verti- 

 cal axii^ of the i»poni;e. I >hall call it tiio " osiculum." From 

 its ed-ii',-, numerous small, irrcj^ular. somttimes branchini» ridges, 

 radiate outwards in all directions over the Hurface, and descend 

 the sides to the hise. Sever.d polished sections, throutjli the 

 o'^euluiu, downward^, siiow tiiat the centre, at least in the upper 

 half, w iH occui>ied by a hirge tubular can il, with smaller ones 

 branching Irom itr. sides, outwards and downwards. This struc- 

 ture ia only indicated by the dark colour of the material which 

 tills tho canals, in contrast with the ii^'ht grey chert, which coq- 

 slitutes tiie mass of the fossil. 



This g'MiiM .somewhat rrseniblcs Anhn-npinm in its structure, 

 but ditrers in having its whole durfure covered with the rounded 



