1845.] across the Peninsula of Southern India. 425 



stone, which at first from their situation and rolled appearance, I 

 thought had been transported from the Ghauts by the river freshes ; 

 but which, on farther enquiry, I found had been discharged as ballast 

 by boatmen from the N. of Bombay, probably from Cutch. 



Some of these fossils are evidently a species of nummulite; others 

 have a singular spiral structure, and spherical globular form, of which 

 my friend Captain Allardyce has favoured me with the following mag- 

 nified drawings. ( See Fig., Diagrams 1 and 2.) 



Of these singular fossils, I shall give Captain Allardyce's description, 

 instead of my own. 



Description of Fig. 1. 



This is a section of the fossil as it is most frequently seen : it shews 

 little of the structure, except that it is convolute in this direction, which 

 leads to the idea of its being a shell, and this a section across its axis 

 or column. 



Description of Fig. 2. 



This is a section of the same shell in the direction of its column : 

 the outer portion is an even fracture towards the centre tending to 

 divide the shell equally ; but the interior portion must be supposed 

 raised and hemispherical, part of the crust having been removed to 

 shew the structure. 



The striae are minute grooves, being the longitudinal sections of a 

 set of capillary tubes that run spirally round the column in number 

 amounting to 50 or 100 all abreast. 



The transverse section of these tubes is seen in the last whorl near 

 the circumference, where they are cut across, and appear in the 

 shape of pores or holes. During each revolution the tubes terminate 

 six or eight times in a general partition, which runs from one end of 

 the column to the other; so that these partitions resemble the divisions 

 of an orange or the valves of a capsule. The tubes can be nothing else 

 than spiral cells, while instead of one as in other shells, there is a great 

 number combined, and it appears as if the animal had been divided 

 into many parts like the corals. The thickness of the crust, as com- 

 pared with the diameter of the cells, is extraordinary ; and in this res- 

 pect also there is a resemblance to the corals and encrinites. 



The exterior shape of the fossil is subglobose. 



3 N 



