270 THE FOSSIL ECHINOIDEA 



There is nothing very marked about the species Echinolampas difflcilis, except its 

 manifest alliance with Echinolampas discoideus, d'Archiac. The proportions, however, 

 diifer, and the general sTiape also. But its details help to maintain the generally 

 depressed character of the Echinolampinae of the Nari series and their alliances with 

 Echinolampas discoideus. Echinolampas d'Archiaci is not unlike Echinolampas 

 Sindensis at first sight ; but the contour and the nature of the margin distinguish it. 



Echinolampas Eadakensis introduces the discoid series, and is one of the trouble- 

 some species which cannot be classified with better-known forms and yet have an 

 indefinite individuality of their own. 



Echinolampas discoideus, d'Archiac, is a very variable form, and, with its varieties, 

 characterizes the Nari series. The specimen used by d'Archiac and Haime, which is 

 in the collection of the Geological Society of London, is one which we should have 

 declined to investigate as a specific type. We have carefully considered the measure- 

 ments of it and of those in the collection from the Nari series, and we consider the form 

 figured in Plate XLI,' Figs. 1 & 2, to be the true Echinolampas discoideus. One of 

 the most interesting varieties of the species is a large form which has the margin in 

 front flattened. Fortunately, in one of the specimens the peristome is well preserved, 

 and we liave given a view of.it. A third specimen shows a worn condition of the 

 peristomial ambulacra, and its delineation (Plate XLI, Fig. 5) certifies to the correct- 

 ness of Loven's descriptions of the relative position of the tentacular orifices. 



The great flat Echinolampas placenta is clearly one of the allies of E. discoideus. 

 It is a most extraordinary form, especially when considered in relation to the great 

 Echinolampas tuniida from the same series. These species are among the largest of 

 the genus, and appear to be confined to the Nari series. 



Euspatangus rostratus, d'Archiac, appears to have a considerable vertical and 

 horizontal range, and the species is found in Kachh. The Nari form certainly has 

 some of the features of Euspatanyus affinis, Duncan & Sladen, from Kachh. 



Finally, Schizaster Oranti, Duncan & Sladen, is found in the Nari deposits and is 

 a common fossil in Kattywar. It passes up into the Miocene series. 



The Oligocene strata of Sind and of Kachh are evidently worthy of the name, 

 and the evidence of their intermediate position between the Eocene and the Miocene 

 is off'ered by the study of the Echinoidea as well as of the Corals. Moreover, the 

 horizon of the strata containing the fossils is not a low one in the series, and there is a 

 slight community of species between the Nari and the overlying Miocene deposits. 



