12 



Remarks on the Genus ConcMcolites of Nicholson. 



Lon. Geo. Mag. They were from the stone quarry on tlie east side of 

 the Avonclale pike, near the top of the hill, at the head of Deercreek. 

 This specimen is a better one than that which Prof. Nicholson had, and 

 clearly shows longitudinal sti'ite under a magnifying glass, Avhicli are 

 barely visible to the naked eye. Wliy the tubes should be called sol- 

 itary I am unable to imagine, for tliey are generally found in clusters, 

 as shown in the figure. Sometimes, however, a single one is found 



Fig. 4. ConcMcolites [Orloiiia) conica. Nicholson. 



loose, or attached to a coral or a shell, or laying flat on a rock. 

 "Whether single or in clusters they are not confined to the shells of 

 "some mollusc," but are found attached to shells and corals indiscrim- 

 inately, and as frequently on a slab, without attachment to either shell 

 or coral, as anywhere else. 



The external surface of the Conchlcolites cornigatus is not destitute of 

 longitudinal strise, as asserted by Prof Nicholson, but, on the contrary, 

 such stride are plainly visible with an ordinary glass on good specimens, 

 and they can be detected with the aid of a good glass on the sj)ecimen 

 belonging to Dr. Hill, wdiich Prof. Nicholson figured and descril)ed. 



So far, then, as the longitudinal strise are concerned, they are com- 

 mon to both the Conchicolites corrugatus, and Conchicolites {Ortouia) con- 

 ica, though the longitudinal furrows may be the most distinct in the 

 latter. No difference, either, can be determined in their social habits, 

 for they are both found in clusters, and though the C. conica is some- 

 times found alone, and the C. corrugatus has not been identified in that 

 position, it does not follow, from any kind of logic, that it may not yet 

 be thus identified. 



They differ so little from each other that the only distinction worthy 

 of a specific name is founded in their method of attachment. Conchi- 

 colites corrugatus seem to attach at the point to some object, and they 

 also seem to adhere together all along the tube. They are found some- 

 times radiating from a point, and so densely crowded together that the 

 upper surface, j)resenting the openings of the tubes, has an ajppearance 



