CLASSIFICATOET POSITION OF SOME MADREPORAKIA. 117 



Sutton stone, and one was clearly the same as that described by 

 Laube from St. Cassian *. The other was specifically distinct, and it 

 had fewer and stouter septa in calices of the same size as those of 

 the other form ; moreover the separation of the corallites was more 

 definite. On due consideration I do not feel disposed to abolish the 

 second species {E. Moorei), especially as a remark in the memoir on 

 " the Madreporaria of the Lias" leads to the belief that its author 

 is not treating of the genus. He compares parts of the corallum 

 with Laiimceandra, with which the types have no affinity. I there- 

 fore retain both of the species of Elysastrcea. 



Genus Montliyaltia, Lmx. 



MONTLIYALTIA SIMPLEX, uobis. 



This species was described and figured in the " Monograph on the 

 Corals from the zone oi Ammonites angulatus,'' p. 9, pi. iii. figs. 16 

 & 17, and is admitted by Mr. Tomes in his criticisms on the corals 

 of the zone ; but a remark is appended to which exception must be 

 taken. It is stated that the " much elongated form of the calice, 

 and the angle observable in some of the septa, are merely the result 

 of pressure." 



The shape is not much elongated, only moderately so, and the 

 cause was the special method of growth of the cycles of septa, ex- 

 amples of which are seen in modern simple corals, such as Caryo- 

 phyllia. The shape of the ends of the septa depends on growth, 

 and is seen in many species even of cylindrical form. The shape 

 has nothing to do with pressure after death. 



MoNTLivALTiA "Walll^, nobis. 



The author of the paper on the Lias corals admits this form, and 

 adds that the describer " might further have noted the continuity of 

 the older septa from the outer rim through the inner wall in the 

 calice proper." In the very next sentence it is remarked that this 

 is "well shown in Prof, Duncan's figure;" but the critic goes on 

 to state that this (Monograph cit. pi. viii. fig. 6) " is a good illus- 

 tration of rejuvenescence." As this expression will have to be con- 

 sidered elsewhere in this reply, it is only necessary for me to remark 

 here that it is nothing of the kind, being an instance of that endo- 

 thecal growth which Lindstrom has called " stereoplasm." 



MoNTLivALTiA POLTMORPHA, Tcrqucm and Piette. 



This is figured on pi. viii. of my Monograph. There is no 

 better example of a Montlivaltia than in fig. 1. Pig. 13 shows 

 two forms springing from the same base. Mr. Tomes, although he 

 admits that he cannot make out the calices of the last-mentioned 

 specimen, because they are (as they were drawn) imbedded in the 

 matrix, places the forms in the genus Thecosmilia, and under the 

 species T. major of De Ferry (op. cit. p. 367). He gives no 



* Monogr. cit. p. 29. 



