443 



off Inveraray, and 3 having been dredged off Strachur by the 

 Rev. Dr Barclay. 



For one of the dredgings from Lamlash Bay I am indebted to 

 Professor AUman ; the others from that quarter were sent to me by 

 the Rev. C. P. Miles, M.D. 



All were more or less interesting. The richest was that of Pro- 

 fessor Allman, which was simply the dirt washed from some nests 

 of Lima hians, dredged in 4 fathoms. One of Dr Miles's was also 

 from these nests in 7 fathoms, and was not so rich, though still full 

 of new forms. Those from Loch Fine were from depths varying 

 from 14 to 60 fathoms. 



No two were alike, except that the two just mentioned,* from the 

 nests of Lima, in nearly the same locality, were more like each other 

 than any of the others. This variety is very curious, when we reflect 

 that over a large extent of the bottom of the Atlantic the recent sound- 

 ings have exhibited an astonishing similarity, being, however, en- 

 tirely different from our estuarial deposits of the Clyde, and very 

 poor in Diatoms. 



The variety just alluded to shows that the deposits of as many lo- 

 calities as possible, even in the same estuary, should be examined, 

 and that we cannot beforehand know what they are likely to yield. 

 It is not at all likely that 11 dredgings, from three localities, and 

 all different, should have exhausted the undescribed forms of the 

 Firth of Clyde. 



I. These materials yielded a very largo number of known species, 

 among which were a good many which have hitherto been extremely 

 rare. Such are, for example. 



Navicula Hennedyi, Sm. 

 „ granulata, Breb. 

 „ Lyra, Ehr. 

 Pleurosigma transversale, Sm. 



„ obscurum, Sm. 



„ delicatulum, Sm. 



„ rigidum, Sm. 



Stauroneis pulchella, /S Sm. 

 Coscinodiscus concinnus, Sm. 

 Eupodiscus crassus, Sm. 



„ Ralfsii, Sm. 



Eupodiscus sculptus, Sm. 

 Campylodiscus Horologium, Sm. 

 Podosira Montagnei, Sm. 



„ maculata, Sm. 

 Orthosira marina, Sm. 

 Surirella lata, Sm. 



„ fastuosa, Sm. 

 Biddulphia Baileyi, Sm. 

 „ turgida, Sm. 

 Grammatophora macilenta, Sm. 

 Syndendrium Diadema, Ehr. 



Perhaps the most interesting among these forms, is Campylodis- 

 cus Horologium, which very few observers had seen, as it had only 

 occurred very sparingly in a dredging made on the Coast of Skye by 

 Mr G. Barlee, and examined by Professor Williamson. I have now 

 a tolerably abundant supply of it, chiefly from Loch Fine, but it 



