240 BULLETIN : MUSEUM OF COMPAKATIYE ZOOLOGY. 



An examination of the original specimens of Duncan in the collection of the 

 Geological Society of London proved that the specimens collected by Mr. Hill 

 at Catadnpa are identical with the Diploria crassolamellosa of Duncan, which 

 a study of Diploria crassolamellosa, Edwards and Haime, showed to be an 

 entirely different species. 



Form, flat, lobed, or subglobose masses. The largest specimen examined 

 (from the Institute of Jamaica collection) is 80 mm. long, 64 mm. wide, and 

 51 mm thick. The series are very long, narrow, and flexuous ; one series may 

 wind around over nearly the entire upper surface of the specimen. The valleys 

 are elevated above the collines, — i. e. the depression between the series is 

 quite deep, sometimes as much as 2 mm. The width of the series is from .5 

 to 1.5 mm. ; 1 mm. is a fair average ; the distance between the series is from 

 1.5 to 3 mm. The whole upper extraserial surface of the corallum is covered 

 with very fine, low, acute equal costae, with granulations on the edges. There 

 are 45 to 48 costse to the centimeter. The septa correspond to the costee in 

 position and number ; they are very crowded, are of the same size, or are 

 alternately slightly larger and smaller. Their upper edges but little elevated, 

 falling in a convex curve to the bottom of the calicular furrow, which is very 

 narrow. Dissepiments are quite numerous. The columella is lamellar, broken 

 here and there by calicinal centres. In longitudinal section it can be seen 

 that the inner edges of the septa fuse by processes placed one above the other 

 to the columella. 



Localities. According to Duncan, Trout Hall and Upper Clarendon. R. T. 

 Hill's collection, Catadupa. A specimen from the Institute of Jamaica is from 

 the District of Clarendon, Parish of Clarendon. 



Types. Museum of Comparative Zoology, Harvard University, and Insti- 

 tute of Jamaica ; specimens in collection of the Geological Society of London. 



Eemarlcs. It is difiicult to see how Duncan ever identified this species with 

 7). crassolamellosa, as Edwards and Haime state : "Largeur des valines, 3 

 millim. On compte environ 18 cloisons dans la longeur d'un centimetre."^ 

 As already noted, the width of the valleys in D. conferticostata is .5 to 1.5 mm., 

 and there are 45 to 48 septa to the centimeter. The spe^es are only ge- 

 nerically related. But the Jamaican form is extremely closely related to 

 Diploria flexuosissima, d'Achiardi,^ from the Eocene of San Giovanni Ila- 

 rione, Italy. In fact they are so near each other that I thought at first the 

 Jamaican form must be considered identical with the Italian form. Reuss* 

 has published a good figure of D. Jlexuossissima, and made some critical notes. 

 For purposes of comparison the greater part of Reuss's description is quoted : 

 " Die Oberflache ist mit schmalen und seichten, sehr langen, vielfach gewunde- 



1 Hist. Nat. des Corall., Tom. H. p. 405, 1857. 



2 Corallarj Fossili del Terrene Nummulitico dell' Alpi Venete, Mem. della See. 

 Ital. (li Sc. Nat., Tom. IV. No. 1, 18G8, p. 2G, Plate XL Fig. 4. 



3 Denksch. d. Wiener Akad. der Wissenscli. (Math.-Wiss.), Bd. XXXIIL p. 11, 

 Plate XXXLX. Fig. 1, 1874. 



