228 PALAEONTOLOGY OF ILLINOIS. 



Hall's name inornata has a better claim to be retained, since 

 not only did its author recognize the fossil as a sponge, but he 

 also proposed a new name for it. The only objection to the 

 adoption of Hall's name is that his description (no figures 

 accompanying it) is not sufficient for the recognition of the 

 species. The form is described well enough by the terms "globose 

 or subglobose," but the statement that "from the point which 

 appears to be the base, there are, in well preserved specimens. 

 a few indistinct radiating lines," is misleading. Of the interior 

 Hall says only that "a transverse section exhibits the charac- 

 teristics of other species of the genus" (L e. Astylospongia); now 

 this statement not only does not aid in distinguishing the spe- 

 cies, but is opposed to the facts, since the Helderberg specimens 

 really belong to Hindia, and the interiors of that genus and of 

 Astylospongia are in no respect alike. 



Hinde's name, Sphserolites nicholsoni, would have been accept- 

 able and appropriate enough had it been established, but as- 

 nothing more than only a short abstract of his paper on the 

 fossil was published, neither the specific nor generic name is 

 available. 



Up to this time only Duncan's work on the species fulfilled all 

 the requirements of proper publication, and, as he was the first 

 to recognize the essential characters of the fossil, and to give 

 us an adequate diagnosis of it, his name Hindia sphseroidalis 

 is justly entitled to be retained for the species. 



From the above we see that the species under consideration 

 was first referred to Calamopora, then to Astylospongia, and 

 subsequently formed the foundation of two new genera. 

 Of the latter, Sphaerolites, as has already been stated, has no 

 claim to recognition, the author of the name having failed to 

 publish his paper, and thus failed to establish his genus. 



There is, however, another generic name that may dispute the 

 title with Hindia. I refer to Microspongia, a genus proposed in 

 1878 by Miller and Dyer. Their description on page 37, vol. I, 

 Jour. Cin. Soc. Nat. Hist., reads as follows: 



"A free calcareous sponge, destitute of an epitheca. The tex- 

 ture is finely porous, without large canals or openings on the 

 surface. Spicules (?) very minute and needle-shaped." 



