68 Miscellaneous. 



50 feet, sloping inwards 11°, beds of sandstone in a sea- worn cave, 

 proving at least one other disturbance in addition. Subsequent to 

 these great disturbing changes, there occurred a series of elevations 

 and depressions, indicated by mixed beaches and sea-bottoms at dif- 

 ferent levels and by the surface of the rock perforated by Lithodomi 

 and sea-worn to the very summit, indicating that the amount of 

 change of level in these comparatively modern times— for the fossils 

 in these deposits are in every case identical with species now living 

 in the neighbouring seas — exceeded the height of the mountain, or 

 1470 feet. There are evidences, also, of a series of movements of 

 depression. All these changes must have preceded the historical 

 period, as previous to the last change, Gibraltar must have been an 

 island, of which there is no record ; the most ancient accounts de- 

 scribing it as it is now. The upheaving forces must have been deep- 

 seated, as there are no erupted igneous rocks near. 



MISCELLANEOUS. 



SUBMARINE EXPLORATIONS BY M. MILNE EDWARDS. 



M. Milne Edwards in a communication to the French Academy- 

 states, that having for some time been occupied in studying the lower 

 marine animals, particularly Zoophytes, Mollusca, Vermes and Crusta- 

 cea, in their living state, on the northern and eastern coasts of France, 

 and being desirous of also entering upon a comparative study of species 

 peculiar to warmer regions, he had visited with this view the shores 

 of the Mediterranean, where their habitats not being rendered access- 

 ible as on the coasts of the Channel and the Atlantic by the alterna- 

 tions of the tide, he had availed himself of the apparatus invented by 

 Colonel Paulin for a course of submarine exploration. He then de- 

 scribes the apparatus, which is a sort of helmet with glass eye- 

 holes, and a flexible tube for a supply of air ; and states, that by 

 its aid, in Provence, Italy, Sicily and Algeria, he often explored 

 the habitations of a multitude of these animals, remaining under 

 water more than half an hour, and at a depth of more than seven 

 metres. 



"Exploring by these means," he adds, "the rocks and the bottom 

 of the port of Milazzo, I procured an immense number of the eggs 

 of mollusks and annelides whose development I wished to study. 

 Besides, I was enabled to catch in the irregularities of the bottom the 

 minutest animals that remain fixed, and cannot be obtained in any 

 other manner. I saw perfectly all that surrounded me, and it was 

 muscular fatigue alone that hindered me from walking at the bottom 

 of the sea just as I could do on the shore. 



" The questions to which I had especially directed my attention re- 

 late to the embryology of the Annelida and of the Mollusca, to the 

 circulation of the blood in the latter animals, as also in the Crustacea, 

 and to the organization of the StephanomitE, and of the Ciliograde 

 Acalephse in general ; but whilst following out these investigations I 

 had occasion to make various observations on subjects of secondary 



