Mr. H. J. Carter on the StromatoporidaB. 319 



chyma as I have done, viz. into " rimdlichen Maschen," our 

 curvilinear, and into '' dreieckigen Masclien," our rectilinear 

 fibre; but in comparing the Stromatoporida3 with the sponges, 

 he evinces an actual knowledge of the former and only a bor- 

 rowed one of the latter ; while even if he had been right in his 

 identification of the two, it would have been better if this had 

 been based on an actual knowledge ofhoth. 



To one well acquainted with the structure of different kinds 

 of Stromatoporidaj it becomes easy, from what I have before 

 stated of their excellence, to identify the whole of his illustra- 

 tions. Thus S. Schmidtii, Taf. iv. and v., from which he 

 takes the character of his " rundlichen Maschen " (p. 7), is 

 evidently a Caunopora which has afforded the character of our 

 "curvilinear fibre," as may be seen from the presence of the 

 vertical spaces or tubes delineated in fig. 2, Taf. v. ; while Stro- 

 ftiatopora typica, Taf. i. and Taf. ii. fig. 1, which has afforded 

 the character of his " dreieckigen Maschen " (pp. 6 & 17), is 

 equivalent in typical structure to what we have assigned to >S'. 

 co7icentnca — that is, our " rectilinear fibre." 8. eleganSj R., 

 Taf. iii. fig. 1, is evidently the " stag's horn " (vulg.) species of 

 the Devonian Limestone, which, of all that I have seen, pre- 

 sents the most beautiful venation internally. But here again I 

 must stop, as this kind of comparison leads to specific dis- 

 tinction, which I propose leaving to the palteontologist. 



With reference, however, to the stelliform groups of vessels 

 called by Rosen " Faserbiischel," and so comparatively over- 

 looked by all preceding and subsequent observers, we find them 

 beautifully delineated, of the natural size, in six specimens out 

 of the ten which he has illustrated ; and where they were not 

 seen, as in S. Ungerni and S. dentata, he suggests (p. 45) that 

 this might have been owing to the ''petrifying process." It 

 might, however, have been owing, as before instanced in 8. 

 granulata (also one of the incrusting species), to their being 

 concealed beneath the superficial layer. Still enough appears, 

 in this admirable "Inaugural Thesis" for his Doctorate, to show 

 that so important a feature in the Stromatoporidte did not escape 

 the intelligent author's notice, while it strongly recalls to mind 

 the equally admirable " Thesis " of Dr. Ch. Barrois on the 

 " Embryologie de quelques Eponges de la Manclie." 



Since this paper was written (1st Sept. 1878), I have re- 

 ceived from Prof. Nicholson and Dr. Murie a copy of their valu- 

 able paper " On the Minute Structure of 8tromatopora and its 

 Allies " (extracted from the 14th vol. of the Linn. Soc. Journal, 

 Zoology). This welcome contribution to our knowledge of the 

 8tromatoj)orce enters so fully into every thing connected with 

 the subject that I can hardly do more than refer to that part 



