192 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



it may be mentioned, were alive, though 2 appeared 

 to have been but recently vacated by the animal. 

 The other species, P. brachystoma, named from its 

 small mouth aperture, has a general West-Highland 

 distribution, for I have taken it in various localities 

 from Stornoway Harbour to Loch Killisport in 

 Knapdale. It had not previously been met with 

 alive in our Firth, and its admission into Mr. Alfred 

 Brown's Mollusca of the Clyde was on the strength 

 of a dead shell dredged in Rothesay Bay. Another 

 interesting species was Rissoa vitrea (Mont.), excluded 

 by Mr. Brown and not included by Dr. Jeffreys as 

 a Clyde form, though Mr. Robertson tells me he has 

 taken it with the dredge between Cumbrae and 

 Largs. Four specimens in all were obtained, and of 

 these one was living. 



A feature of the ground of our operations was 

 the large number of immature specimens of three 

 of the bivalves, viz., Nucula nitida, G. B. Sow., iV. 

 tenuis (Mont.), and Scrobicularia nitida (Mull.), tiny 

 examples of these occurring in some abundance. 



Regarding the day's record of species met with, 

 partly in the sieves and partly by subsequent 

 examination of the dried siftings, I have to report 

 as follows, viz.: 



Lima elliptica, Jeff.;— one fine live adult. 



Nucula sulcata, Bronn; — one young live, and 



valves. 



nitida, G. B. Sow. ; — a few adult ; young 



plentiful. 



TENUIS (Mont.); — fairly numerous; young 



plentiful. 



Montacuta bidentata, Mont.; — rather common. 



Axinus flexuosus (Mont.) ;— several, both adult and 



young. 



Cardium minimum, Phil.; — 4 young live examples 



of this rather local 

 species. 



Scrobicularia nitida (Mull.) ; — some at each haul ; 



young abundant. 



