KATURAL HISTORY SOCIETY OF GLASGOW. 35 



It is found that each sjiecies selects that kmd of material which 

 accords with its own particular habits ; but the departure from 

 the common rule is often considerable, where the supply of proper 

 materials are not within reach. In such cases they avail them- 

 selves of the next best, and failing such, some of the species fall 

 back on the resource of constructing a tube solely from their own 

 secretion. These shifts often give the structure a very different 

 aspect from its common appearance, and one that is ready to 

 mislead as to the true character of the occupant. 



But whatever straits or shifts they may be driven to, or what- 

 ever kind of materials they may use, whether the consolidation of 

 soft mud into tubes, the picking out of fancy stones to cover the 

 walls of their habitation, the laying of each piece so as to " break 

 band," the overlapping the materials of the walls like the slates 

 on a house, the construction of the edifice with fine mosaic work 

 or with plain rubble, the same line of structure of each species is 

 rigidly adhered to. 



Mr John Young, F.G.S., stated that probably never had such 

 an interesting series of tube-building annelids been exhibited 

 before any Society in this country as those laid before the 

 meeting on this occasion, and they were the more interesting from 

 the fact that they had all been obtained by Mr Robertson's own 

 dredging, chiefly from the Frith of Clyde. The group had 

 hitherto been little studied, and probably many other species 

 await further exploration in the seas around the Scottish coasts. 

 Mr Young hoped that Mr Eobertson would still continue his 

 researches among the less known marine fauna, as only from 

 the investigations of able naturalists important information like 

 that embodied in Mr Eobertson's paper is to be obtained. 



December 2Sth, 1875. 



Mr James liamsay, Vice-President, in the chair. 



Mr Arthur Pratt was elected an ordinary member of the 

 Society. 



Mr J. B. Murdoch called the attention of the meeting to the 

 death, after a long illness, of Mr James H. Pearson, who had for 

 many years been a member of the Society. He had for a 



