and Littoral Manganese Nodules 173 



grain of sand. This shows conclusively that the nodules have 

 not been washed down into their present position; and that 

 they have been formed in situ is further shown by the fact that 

 the mud round tlu-m is generally stained yellow with ferric 

 oxide. A number of nodules were picked out for illustration 

 and analysis. 



In the Plate, fig. i represents a nodule which was found 

 attached to the rim of a dead pecten shell. It is represented 

 in one and a half times the natural size. 



Figs. 2 and 2A represent, in twice natural size, a nodule 

 entirely filling up a shell. 



Figs- 3. 3 A > an d 3 B represent, in twice natural size, (3) a 

 nodule found attached to a dead pecten shell; (3A) the under 

 side of the nodule, showing bases of attachment; and (36) a 

 view of the shell, showing surfaces of attachment. 



Fig. 4, in one and a half times natural size, shows a remark- 

 able nugget-shaped nodule. 



Fig. 5, in twice natural size, shows a pear-shaped nodule, 

 with stem of attachment. 



Fig. 6, in twice natural size, shows a spherical nodule of 

 the commonest form. 



Figs. 7 and 7 A show a nodule split through the middle, and 

 with a semi-detached nucleus. The half of the kernel pro- 

 trudes in fig. 7, and the corresponding cavity is visible in 

 fig. 7\. 



All these nodules were got on 2ist September 1878. 



The nodules taken for analysis are as follows: M and N 

 (call [0 and 14 in original notes) were chosen as ave 



specimens. I' was a rather softer and Q a rather more stony 

 nodnle. A" and A' are the kernel- and rinds respeetivelv of 

 five nodules. These nodules were split, and the kernels and 

 rinds separated as carefully and as completely as possible. 

 Their approximated weights were: 



Kind- . . [O7XO 



Total .. KI*837 



S is g sample taken li"in a number of nodules pounded, 



up and mixed. 



