438 Proceedings of the Royal Physical Society. 



skin and cause irritation. It was remarkable to see how, 

 when this creature was touched, it bristled up like a hedge- 

 hog. Among the Sedentaria, a small form, with tubes of shell 

 fragments, was found adhering to the under surfaces of 

 stones ; a fine Salella with dark red gill plumes, which 

 inhabited the mud tube attached to the under side of the 

 reef shelves; a most magnificent Serpula, with a curved 

 spine over the aperture of its calcareous tube and of gorgeous 

 colour, was also observed. The Mollusca were not numerous, 

 except limpets, of which we saw several kinds. Many shells 

 belonging to this order we found to be tenanted by hermit 

 crabs. A species of oyster was found firmly adhering to the 

 reef by a single valve. A small Aplysia was abundant, as 

 was also a species of octopus. Asteroidese were entirely 

 absent. There are many sponges; their skeletons, thrown 

 up on the beaches, would frequently do very well for bath 

 use. 



In regard to climate, we found the temperature exceedingly 

 equable, and we had an almost constant breeze day and night. 

 In the end of August and beginning of September many very 

 heavy showers fell, but later, these got much less frequent, 

 and the place began to get rather dessicated; and the herbage 

 which, on our arrival, had been of a brilliant green, was 

 observed to dry up. We were told that in ISTovember and 

 December the herbage is entirely withered through drought, 

 but in February heavy rains set in. We enjoyed most 

 excellent health all the time we remained upon the island. 



XXXVII. On a New Eurypterid from the Upper Coal-measures 

 of Badstock, Somersetshire. By B. K Peach, Esq., 

 A.RS.M., F.E.S.E. [Plate XX] 



(Read 15th February 1888.) 



Among Palaeozoic Arthropods none have a greater interest 

 to the biologist than the Eurypterida. During the deposition 

 of the Silurian and Old Red strata of our country, aquatic 

 genera of this family abounded, and from the nature of the 

 matrix in which their remains were embedded, almost com- 



