180 BRITISH STROMATOPOROIDS. 



certainty, the specific name given by Phillips would, strictly speaking, have a claim 

 to be retained, and the species would stand as Stromatopora placenta, Phill. sp. 

 Upon full consideration, however, I have decided to retain Bargatzky's name for 

 this species upon two grounds — viz. in the first place, that the description and 

 figures given by Phillips of his Caunopora placenta are entirely insufficient to 

 determine clearly the form which he had under consideration, and, in the second 

 place, that the " Caunopora-tubes " are made an essential part of the diagnosis of 

 the species. If the original specimen of Phillips were examined, it is very 

 possible that it might prove to be referable to what is here understood as Stromato- 

 pora Hiipschii, Barg. It might, however, prove to be a " Caunoporised " example 

 of 8. Beuthii, Barg., or 8. BucheUensis, Barg., and, indeed, I am rather disposed 

 to think that it is to the last-named of these that it really belongs. At any rate, 

 the original figures and descriptions would fit the one hypothesis quite as well as 

 the other ; and under these circumstances it seems to me best to allow the name 

 of Caunopora placenta, Phill., to fall altogether. 



On the other hand, the Caunopora placenta of Bargatzky himself — as I have 

 established by an examination of the original specimens — is really identical with 

 the Caunopora Hiipschii of the same author ; and in order to avoid confusion with 

 the fossil described by Phillips as C. placenta, the second of Bargatzky's specific 

 titles must be retained. As I have shown previously, however, Bargatzky was 

 led into a misconception of the true nature of the genus Stromatopora by reason 

 of his ignorance of the minute structure of 8. concentrica, Goldl, the type-species 

 of this genus. The Stromatopora of Bargatzky is thus really what I have named 

 Actinostroma, and the Caunopora of this author is really Stromatopora. The 

 present species, therefore, under the circumstances just recounted, may best 

 stand as Stromatopora Hiipschii, Barg. sp. 



The Stromatopora Beuthii of Maurer (loc. cit. supra) appears to be founded 

 upon a specimen of 8. Hiipschii, Barg., without "Caunopora-tubes," while the 

 8. indubia of the same author seems to be S. Hiipschii 'with "Caunopora-tubes." 

 The S. maculosa of Maurer may also be referable to S. Hiipschii, but its preserva- 

 tion is bad, and its true affinities are doubtful. 



Distribution. — 8. Hiipschii, Barg., appears to be entirely confined to the 

 Devonian Rocks, occurring with great frequency in the Middle Devonian Lime- 

 stones of both Britain and Germany. In the latter region it occurs abundantly at 

 Biichel, in the Paffrath District, but appears to be wanting at Hebborn (where 

 8. Beuthii, Barg., is common), while it is a rare species at Gerolstein. In the 

 Devonian Limestones of Devonshire it is the commonest of all the forms of 

 Stromatopora, occurring usually in the " Caunopora-state." Large and perfect 

 examples are found at Dartington (Pit-Park Quarry), while others are found at 

 Bishopsteignton, and the species is exceedingly abundant in the pebbles of 



