1848.] LONSDALE ON FOSSIL ZOOPHYTES. 67 



Were the lower greensand fossil to be studied solely with reference 

 to the surface, little doubt might be entertained respecting the cor- 

 rectness of the published determination ; but it is necessary to in- 

 quire what may be the internal composition of the typical species of 

 Heteropora, and the amount of agreement with the English coral. 

 Of M. Goldfuss's figures, only one exhibits a distinct interior ; and, 

 unfortunately, it was not drawn from the same specimen as that 

 which supplied the enlarged surface ; but the coral, H. anomaloporoj 

 is stated, as well as //. cryptopora (Petref. p. 33), to consist of 

 tubes. Of the composition of the third, //. dichotoma, no informa- 

 tion is clearly afforded in the figures, and it is not alluded to in the 

 descriptions. The two first species may however be admitted to be 

 tubular and not cellular corals ; and from M. Goldfuss's figure 5 b 

 (pi. 10) it may be inferred, that the larger openings are only termi- 

 nations of tubes. As respects the minor pores, the great uniformity 

 of size represented in the delineations quoted (fig. 3c and fig. 5^/), and 

 the equality in the dimensions of the large aperture as well as the 

 distinctness of character in each case, impress the belief that the 

 minor openings can hardly be regarded as young interpolations, but 

 that they belonged, as M. Milne-Edwards suggests, to a peculiar, 

 subordinate structure. M. Lamouroux's two species of Millepora* 

 exhibit however, in the enlarged representation, so great a diversity 

 of size in the openings, and Vv^ant of separableness into two sets, that 

 there is no difficulty in supposing the smaller may be the mouths of 

 young tubesf . Again, in the fossil described by M. Roemer under 

 the term Heteropora verrucosaX, the secondary apertures have so 

 symmetrical an arrangement, that they imply very distinctive pro- 

 perties in the inhabiting polypi ; while in some of the Heteroporse 

 beautifully figured in M. Michelin's work§, the minor pores greatly 

 resemble lacunae, and, therefore, indicate other peculiarities in the 

 constructing animal. It is not necessary to allude to additional ex- 

 amples, enough having been given to show that " two sorts of pores" 

 are an insufficient basis for a genus. Two of the fossils described in 

 these notices, the one under consideration, and Siphodictyiun gracile, 

 possess most markedly large and minor apertures, but so far from 

 being referable to one genus, they belong to widely-distinguished 

 classes. Nevertheless, M. de Blainville was fully justified in sepa- 

 rating the three fossils from Ceriopora ; but it remains to be ascer- 

 tained whether they are to be received as types of one genus or of 

 more than one. 



The character, " couches enveloppes," is not insisted upon by M. de 

 Blainville, being borrowed from Prof. Goldfuss's description of Cerio- 

 pora (Petref. p. 32) ; as the lower greensand coral however possesses 

 such a structure, it must not be passed over in silence. The term 



* Op, cit. pi. 82. fig. 8, pi. 83. fig. 7. 



t M. Michelin has described under tlie terms Ceriopora dumetosa and C. coni- 

 fera, fossils which he identifies witli Lamouroux's Milleporse, and the figures have 

 only one kind of pores. Iconog. Zoophyt. p. 245. pi. 57. fig. 1 a,b; fig. 8 a, b. 



% Verst. Norddeuts. Kreidegeb. tab. 5. fig. 26g,S. 



§ Iconographie Zoophytologique, pi. 57. figs. 2, 3, 4. 



f2 



