88 Mr II. GooJsir on the Sexes of the Clrrlpcds, ^c. 



appearance the beach hero seems to end, but in reality the 

 boulders are found in a decomposing state, and bedded in the 

 loam resulting from that decomposition, for at least 20 feet 

 above the present highest tide-mark. The grassy part has 

 also the same slope and contour as the uncovered part of the 

 beach. In cutting through this bed for a road, I found, at a 

 depth of 4^ feet below the surface, cockle, periwinkle^ and 

 other shells, which still inhabit the neighbouring shores. 



Here, then, is a beach whose level and appearance prove 

 the gradual elevation of the island. Unlike many other similar 

 relics of the sea that are found without anything intermediate 

 to substantiate the connection, this beach presents an uni- 

 form continuation of the existing shore to the height of 20 

 feet above the range of the highest tides, and thus would seem 

 to afford strong presumptive evidence, that the land at this 

 place does, or at least did, gradually emerge from the ocean, 

 the general shape and contour of the present bays being easily 

 recognisable on the grass-grown land. 



I am sensible that the foregoing observations are in some 

 respects but very imperfect, yet I feel justified in giving this 

 sketch, as the facts which happened to come under my notice 

 seem to favour the conclusion that the Silurian system, as 

 characterized by Mr Murchison in his work on the Silurian 

 System, exists in Scotland. 



On the Sexes, Org at^s of Reproduction, and Mode of Development, 

 of the Cirripeds, Account of the Maidre of the Fishermen^ 

 and Descriptions of some New Species of Crustaceans. By 

 Henry D. S. Goodsir, Esq. Communicated by the Au- 

 thor. With three Plates. No. V. 



SECT. I. ON THE MALE OF THE BALANUS. 



It has hitherto been a question whether the sexes in the 

 Cirripeds are distinct as male and female, or are combined in 

 the same individual ; and the opinions which have originated 

 from this, are both very numerous, and at the same time contra- 

 dictory. No two authors agree as to the anatomy and physio- 



