MINUTE STRUCTURE OF STROMATOPORA AND ITS ALLIKS. 195 



General Structure of a Typical Stromatopora. 



If we take a typical species of Stromatopora, sucli as S. con- 

 centrica, Gold., of tlie Devonian, we find that it presents itself 



Pig. 1. 



Stromatopora rugosa. 



A small and perfect, specimen, of the natural size, from the Trenton Limestone 

 of Canada. (After Billings.) 



Dr. Steinmann has published a memoir, "Ueber fossile Hydrozoen" [Palffi- 

 ontographica, n. F. v, 3 (xxv.), p. 101], in which he refers Stromatopora to the 

 Hydractiniidae, and as being structurely similar to his new genus Sphcer actinia. 



Mr. Carter expresses the opinion that Stromatopora is identical in structure 

 with the recent Millepora alcicornis (Ann. & Mag. Nat. Hist. ser. 5, vol. i. p. 298). 

 A perusal of Mr. Carter's remarks will at once show that in speaking of " Stroma- 

 topora " he is really alluding only to the curious and aberrant Caunopora. In a 

 secmd paper (ibid. p. 412) Mr. Carter announces that he has detected " hexac- 

 tinellid structure " in Stromatopora from Devonshire, and in a third (ibid, 

 vol. ii. p. 85) he says that the form presenting this structure is S. concentrica, 

 and that he has determined this to be really Caunopora, Phill. 



In a paper on the Microscopic Structure of the Stromatoporidae, not yet pub- 

 lished in full, Principal" Dawson gives grounds for believing that the Stromato- 

 poroids are truly Foraminiferal, and are the Palaeozoic representatives of Eozobn 

 (Abstract, Proc. Geol. Soc. No. 3.55, p. 4). 



Finally, Mr. A. Champernowne (ibid. p. 5) gives an account of the Stromato- 

 poroids of Devonshire, and his views as to their structure and nature. 



