FRENCH GONIOPORA. [39 



running in a pronounced wavy or zigzag pattern. Some 20 septa spring from the walls, quite 

 short at the margin but gradually lengthening below. They are very wavy and angularly 

 bent, nearly all smooth but of varying thicknesses. Their arrangement is obscure, for they 

 soon join a ring of synapticulre which seems to mark the boundary of a loose columellar tangle. 

 Between the wall and this tangle there is frequently a ring of open, interseptal loculi, many 

 of them nearly circular. The columellar tangle shows no special closeness of its reticulum, 

 but lias large rounded meshes like the interseptal loculi. Immense numbers of tabulae are 

 developed, and the fossa? appear to have been shallow, i. e. tabula? began to appear very early 

 among the meshes of the columellar tangle. In fig. 2 these show at the surface more 

 conspicuously than in fig. 1. 



There are two specimens ; the larger, without definite locality, came originally from Pro- 

 fessor Milne-Edwards with a label upon it " Poritea DefUmyesiana, Michelin." Milne-Edwards* 

 wished to identify Michelin's coral with a Litharcea. But if Michelin's figure t is correct in 

 its main details it was a true Porilcs, while the coral above described is a true Goniopora. 

 Milne-Edwards' description seems to have referred entirely to Michelin's figure, but why did 

 he call it Litharcea 1 Perhaps he had this or some kindred specimen in mind which he 

 incorrectly identified with Michelin's coral. Once more we have to note that the confusion is 

 due to the attempts to group into species, which these great naturalists were compelled to 

 make by the prevailing system. 



The specimen is large, and from the number of boring molluscs is probably a fragment of 

 a very massive stock. The surface is all worn down so that the calicles look flush with the 

 surface ; but the number of portions of tabula? which show at the surface are evidence that we 

 are looking at sections. In one place only, where an original surface was apparently grown 

 over by a fresh layer and uncovered again by a fracture, do we see what may have been the 

 original walls, and it is from this small part that I have, though with some hesitation, given 

 the details in the description. The illustration is from the worn surface. 



The smaller specimen, said to be from Auvers, and with smaller calicles, seems to have 

 been part of a worn pebble : it shows essentially the same characters, only the intersepta 

 loculi and the meshes of the columellar tangle are smaller. The traces of boring molluscs are 

 visible, suggesting that this specimen also originated from a large massive stock. The tabula? 

 are the most conspicuous skeletal element of the worn surface. 



The larger specimen was transferred from the Museum of Practical Geology in 1880. 



Forms of similar horizon and very closely allied to this are found in La Manche, see 

 G. Coutances 1, but the growth-form is very different. Those which now follow and still 

 belonging to the Paris Basin are also allied, in that they all have the lamellate septa with 

 smooth top edges ; but each has an aspect of its own. 



a, b. Geol. Dept. R. 4822 and R. 4823. 



L34. Goniopora Paris Basin (14) 11. (PL X°. fig. 3; PL XIV. fig. 12.) 

 [Auvers (Upper Eocene) ; British Museum.] 

 Description. — Corallum forms irregular convex masses tending to overhang the base of 

 attachment. The surface is quite smooth. 



* See Hist. Nat. Coralliaires, iii. (1860) p. 187. | Icones, 164, pi. xlv. fig. 4. 



T 2 



