1848.] LONSDALE ON FOSSIL ZOOPHYTES. 63 



noticed, and it has been reserved for a more direct comparison, be- 

 cause it is the only figured organic body known to the author which 

 apparently partakes of the structures and mode of growth of the 

 Atherfield fossil. The natural size of M. Goldfuss's example of A. 

 costatum (he. cit.) is four lines, or nearly that of a specimen of the 

 Atherfield fossil presented to the Geological Society by Capt. Ibbetson, 

 F.G.S. The Streitberg sponge is described (p. 94) as almost hemi- 

 spherical, and to be distinguished by nine projecting ribs, which 

 radiate from the apex to the base, and always widen downwards. 

 The web is stated to consist of thick, curled, loosely interwoven fibres, 

 and waved rind-like laminae are mentioned as occurring near the base. 

 A comparison of the Atherfield fossil (fig. 1) with M. Goldfuss's en- 

 larged representation, and with his description, will establish an almost 

 perfect general agreement, due allowance being made for the simple 

 radiation of the ribs in one case, and for the contorted distribution in 

 the other. Viewed under an ordinary pocket-lens, the Atherfield 

 production will be found to be indented and pitted similarly to that of 

 Streitberg (Goldf. pi. 34. fig. 7) ; and at the base of a fine specimen 

 in Dr. Eitton's cabinet was noticed a largely-developed thin lamina 

 (fig. 1). A distinction exists between the two fossils in the degree 

 of downward thickening in the ribs ; but this want of conformity, as 

 well as the different arrangement of that structure, can be considered 

 but specific variations. M. Goldfuss clearly regarded the secondary 

 ridges as fibres, and the lacunse as meshes ; in the Atherfield speci- 

 mens however, and from apparent analogy most probably in those 

 found near Streitberg, the secondary ribs are not simple but com- 

 pound structures, pierced by minute pores, and the lacunae are inter- 

 blended or circumscribed channels. From what has been already 

 stated, it is evident that the Atherfield sponge does not possess the 

 characteristics of Tragos, Manon, or Achilleum, nor can it be referred 

 to any other genus known to the describer. It is therefore proposed 

 to distinguish the English Amorphozoon by the term Conis (KoyiSy 

 pulvis), in allusion to the apparent pulverulent condition of the cal- 

 careous matter ; and it is further proposed to include under the same 

 generic name, but provisionally, Ack. costatum (C. costata). 



Conis, n. g. 



Gen. char. — Fixed, polymorphous, formed of variously- disposed ridges, 

 blended towards the base into a uniform mass ; the whole surface 

 of the ribs and intervals lacunose, or indented by vertical and con- 

 necting channels : spaces between lacunae minutely porous : con- 

 stituent material calcareous, very finely grained (?), including a 

 fibrous reticulation. 



Conis contortuplicata, n. sp. 



(Plate IV. fig. 1 to 4.) 



Spec. char. — Ridges variously tvdsted and anastomosed, irregular 

 in form ; the lacunae or channels, invisible to the unassisted eye *, 



* It is perhaps requisite to state, that a Codrington lens or a Hooker's micro- 

 scope was found necessary in attempting to ascertain the structures of this fossil. 



