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The author was not inclined to regard the process of gemmation, 

 which is the more frequent mode of multiplication in these animals, 

 as explicable on the supposition that the buds are developed from ova 

 that have been previously impregnated, and are retained in the sub- 

 stance of the parent's body. 



2. On the Parallel Roads of Lochaber ; with Remarks on the 

 change of relative Levels of Sea and Land in Scotland, 

 and on the Detrital Deposits in that Country. Part I. By 

 David Milne, Esq. 



The author, after referring to the views of former observers, 

 stated, that though he had proceeded to Glen Roy under a strong im- 

 pression that Mr Darwin's marine theory afforded a solution of the 

 question, he had felt himself constrained, after an examination of the 

 valleys, to abandon that theory, and that he had satisfied himself 

 that the shelves had been formed by lakes of fresh water. He re- 

 ferred to the proofs still existing of the mode in which these lakes 

 had been discharged, and he described particidarly the unequivocal 

 traces of an old river course running from the head of Glen Glaster 

 to Loch Laggan, with a delta at the level of shelf 4 on Loch Lag- 

 gan side, formed by this ancient but now extinct river. 



The author considered that the blockage of the waters in the 

 valleys had been formed of boulder-clay and other ancient detrital 

 matter. There was proof that this detritus had been deposited in 

 the district before the waters had begun to be depressed, as the 

 shelves were, in some places, indented on the boulder-clay ; and this 

 detrital matter must, when deposited in the valleys, have been in 

 sufficient quantity to have dammed back the waters, as there were 

 still abundant traces of it on the sides of the hUls at a higher level 

 than that of any of the shelves. 



The author differed from Dr MacCuUoch and Sir Thomas Dick 

 Lauder, in supposing that it was necessary to assume the occurrence of 

 an earthquake or any convulsion of nature to account for the breaking 

 down of barriers, by which the lakes were blocked up. He con- 

 sidered that it was an error to assume that the first depression of the 

 lake in Glen Roy was 82 feet, and shewed that there must have been 

 at least three intermediate depressions ; and that after the first de- 

 pression, the water must have flowed out by Glen Glaster into Glen 



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