104 PROCEEDINGS OF THE 



bird; but Mr Alston observed tliat limited numbers remain in 

 various Scotch localities both on the eastern and western shores, 

 an opinion shared in by Mr Gray, the Secretary, who stated that 

 he had observed this gull repeatedly in the Firth of Clyde in raid- 

 winter. 



Mr Thomas Chapman exhibited a small case of moths recently 

 obtained from New York; and Dr Scouler exhibited specimens of 

 the Axolotl, giving some account of the structure of that curious 

 animal. 



Mr Alexander M'Kinlay exhibited sj)ecimens of Mnmm sjnnosum, 

 a new British moss from Ben Lawers, where he had first gathered it 

 in 1861. 



PAPERS READ. 



I. — Notes on CoropJiium Longicome, and on the occurrence of Alteutha 

 Bopyroides. By Mr David Eobertson. 

 Mr Spence Bate, in his work now being published on the British 

 Sessile-eyed Crustacea, says of Corojihwm longicome: — "It dwells 

 in tubular galleries, excavated in the mud over which the tide 

 flows and ebbs. It has not, however, been ascertained whether the 

 channels in the mud are perforated by these Crustacea, or by the 

 numerous annelids that they prey upon." He likewise quotes 

 Quaterfages in his pleasant " Eambles of a Naturalist," where he 

 says, at Saintonge: " About the end of April they come from the 

 open sea in myriads to wage war with the annelids, which they 

 entirely destroy before the end of May. They then attack the 

 mollusca and fish, all through the summer, and disappear in a 

 single night about the end of October, and return again the 

 following year." In order to test the accuracy of these obser- 

 vations, I put a number of them in a vessel with mud, and 

 soon saw that they had the power of burrowing. In doing 

 so they bring the points of their long antennae together, and 

 push them into the mud; the fore feet help in widening the 

 hole, and in turning the mud side-ways; the hind feet throw it 

 backwards; the tail is placed nearly at a right angle downwards, 

 which it presses against the excavated mud, and forces itself 

 forward. Last summer, at Oban, I found them burrowing in stiff 

 blue clay. On digging a portion of it up to ascertain the depth of 

 their perforations, I discovered that each burrow was provided 

 with two openings; the one shaft descending perpendicularly. 



