ASTROC(ENI^ OP THE SUTTON STOKE. 109 



I therefore refer it." As no reasons relating to the morphology of the 

 forms are given, the following facts may 'show that the two species are 

 perfectly distinct and belong to different genera. It is right that I 

 should state that since this synonymy has been asserted, I have 

 again carefully examined my old type at Bath. Its calicos are one 

 half of the dimensions of those of S. Martini, and the cyclical arrange- 

 ment of the septa seen in the Stylastraean is not present in the 

 Astrocoenian, which has the usual ten long and ten short septa of adult 

 Astrocoenice. The method of gemmntion differs in the forms, and the 

 projecting calice of the St3^1astr8ean and the exotheca between its 

 walls are not present in the Astrocoenian. Astrocoenia superha, nobis, 

 is therefore distinct from the form described by M. de Fromentel, 

 a form with which I was acquainted when I wrote the Memoir for 

 the Palaeontological Society in 1867. 



AsTEOC(ENiA MiNUTA, uobis, op. cit. p. 22, pi. ix. figs. 18-20. 



The polygonal corallites, rarely with circular and usually with 

 polygonal calicos, separated by no great amount of united wall, are 

 thoroughly Astrocoenian. The calicos are small and deep, and they 

 do not project after the manner of Stylastrcea ; on the contrary, they 

 are separated by raised edges and are deep. The paliform teeth 

 which were described by me, are large and are on the septa, and 

 the columella is small. There is no better example of an Astro- 

 coenian, and it is impossible to admit the species into a genus with 

 which it has no alliance. The species has been called a Stylas- 

 traean in the critical essay mentioned above, and the resemblance 

 to a Stylina from Azzarola and to the typical species of Haldonia, 

 nobis, has been asserted in the same communication. The paliform 

 teeth were mentioned by me, and the small size of the calicos also 

 as the distinctive characters, although this does not appear from the 

 'criticism of the corals of the White Lias, &c. p. 371. 



It is stated there that " both show a remarkable resemblance in the 

 above respect to the coral from the Greensand of Haldol], which has 

 been made the type of the genus Haldonia by Prof. Duncan." The 

 words "above respect *' refer to "the paliform tooth on each septum 

 in close proximity to the columella." Now in the first place, in its 

 structural characters, Astrocoenia minuta is generically distinct from 

 any Stylina from Azzarola, and it is evident that if the form 

 were a Stylina, it could not possibly be placed in the genus Stylas- 

 trcea. Then it is to be noticed in the description and drawing of 

 Haldonia Vicaryi, nobis (Quart. Journ. Geol. See. vol. xxxv. p. 91, 

 pi. viii. figs. 2, 3), that there are pali before the primaries. The pali, 

 as seen in the plate, are remarkable for their rugged sides, and they 

 are not paliform teeth or appendages to the upper and inner parts 

 of septa, but independent structures. There is therefore no struc- 

 tural resemblance between the paliform teeth of Astrocoenia minuta 

 and the true pali of Haldonia, a genus which is moreover different 

 from Astrocoenia, for it has no columella and the dissepiments are 

 almost tabulate. 



I replace Astrocoenia mioiuta, nobis, in its original position. 



