320 Mr. H. J. Carter on the Stromatoporidse. 



which bears upon the humble object of mj communica- 

 tion. 



In the first place, I wish the typical ioxraoi Stromatopor a ^xy&a 

 at p. 195 had been taken from Mr. Vicar j's specimen obtained 

 from the Devonian Limestone near Newton Abbot, instead of 

 from the specimen from the Lower Silurian of Canada " repre- 

 sented in Dr. Dawson's ' Dawn of Life,' as the former is almost 

 perfect, and the latter extremely imperfect and much weathered. 

 (A short description of Mr. Vicary's specimen has already been 

 given.) As for the statement in \\\q footnote at the bottom of this 

 page, viz. that I had identified Stromatopora with Gaunopora^ 

 what I meant to be understood was that Caunopora was the 

 species of Stromatopora to which I had all along alluded, and 

 that the so-called " hexactinellid structure " I had found in S'. 

 concentrica, raihi. I agree in toto with the authors at p. 201, 

 where they conclude that the " Stromatoporoids were originally 

 calcareous in their composition,''' also (at p. 203) that the " radial 

 pillars " (our vertical lines or rods) were " solid," as I have 

 already stated. At p. 209, the " radiated water-canals " are 

 the stelliform groups of canals or branched vessels of our " pro- 

 liferous membrane," equivalent in part to the hydrophyton of 

 Allman whose contents and surroundings I have shown to have 

 probably been nucleated cells ; and, at p. 210, 1 must consider 

 the " vertical water-canals," where not calicular tubes, to have 

 been the canals of Annelids, with which the Stromatojjorce were 

 evidently infested, like Millepora alcicornis — which is equally a 

 prey to the boring sponge Cliona, whose cavernous excavations, 

 connected by little thread-like canals, often give the coral a 

 lacunose structure. It is with pleasure that I see (p. 217) 

 that the specific descriptions and arrangement are only " pro- 

 visional," as it affords a prospect of still more valuable infor- 

 mation coming from the same source; while I feel convinced 

 that until authors, who can never see all the type specimens, 

 have the opportunity of seeing good representations of all the 

 well-marked typical species (not like Stromatoptora concentrica^ 

 Golclf. &c.), the nomenclature and arrangement of the Stro- 

 raatoporidas will remain in confusion. Thus, as regards the 

 former, we have a Stromatopora mammillata^ F. Schmidt, of 

 1858, apud Rosen, and a Stromatopora mammillata^ Nicholson, 

 of 1878, pi. i. fig. 10 ; again, there are other species figured 

 in Rosen which appear to me, who possess such from the Devo- 

 nian Limestone, to be figured by Nicholson and Murie under 

 different names, &c., and so on. 



I cannot admit any one of the " grounds " (a-e inclusive, 

 pp. 228, 229) urged by the authors against my view that Par- 

 heria was allied to Stromatopora^ for reasons already pub- 



