Genus Pasceolus. 5 



hexagonal instead of quadrilateral plates. I do not see, however, 

 how the net-work figured by ^Nlr. Pengelly can be made to fit hex- 

 agonal plates, in the way that the squares formed by the stolons of 

 ReceptacvMes are adjusted." 



"M. M. Edwards and Haimehave referred Eichwald's genus Cydocri- 

 nus to the Zoantharla. Whether they are right or not with regard to 

 the Russian species, I can most confidently a,ssert that Pa^c^.olm is 

 not a coral. It may be allied to Meceptaculites, but its true zoological, 

 position is quite undecided at present." 



In describing the P. Halli, he says : '.'A little below the mid-height 

 of the body there is a small circular elevation, which appears to mark 

 the place of an orifice ; but as the integument is not preserved in this 

 part, it c\n not, at present, be positively determined whether there was 

 an aperture here or not. All that can be said is, that there appears to 

 have been an orifice where this elevation occurs. The specimens 

 collected are all casts of the interior, but of the one figured a portion 

 of the integument remains attached to the matrix. It is about one 

 third of a line in thickness, of a translucent horny color, the surface 

 covered with niinute corrugated wrinkles, just visible to the naked eye. 

 No sutures can be distinguished, and the form of the plates can only 

 be made out as so many obscure convexities on the outside. But, 

 where the integument is removed, the cast shows the place of the sut- 

 ures most distinctly, and that the plates were deeply concave on the 

 inside." 



The LunuUtes (?) dadloloides, of Owen, which was -placed provision- 

 ally in the genus Pasceolus by Meek and Worthen (111. Geo. Sur., vol. 

 iii., page 345), is found in the Niagara group of the Upper Silurian, 

 and the pits on the convex side are described as of "uniform size, and 

 each one perforated in the middle by a minute circular opening, pass- 

 ing into the interior ; while those of the under or flat side are imper- 

 forate, and diminish in size from the periphery toward the center." 



Pasceolus Darwini.—(S. A. IVIiller.) 



Upper half of body hemispherical ; lower half slightly depressed 

 from the hemispherical form, and having a central circular depressiju 

 marking the place where the column or pedicle that supported the 

 body was attached. In casts, the entire surface is marked by closely 

 crowded pentagonal and hexagonal depressions, about a line in 

 diameter, in specimens IJ inches in diameter. 



Usually compressed, so as to show a somewhat angular periphery, 



