GLASGOW SOCIETY OF FIELD NATURALISTS. 41 



short grasses at Tollcross. Also a specimen of Nematus Wttewaalli, 

 Yoll., a saw-fly not hitherto mentioned as a native of Britain. It 

 had been bred from larvae found not uncommon at Cadder 

 Wilderness, feeding on willows; they emit a very offensive odour. 



Mr. Middleton exhibited some beautiful small shells from the 

 West Indies. 



Mr. Pearson exhibited a living specimen of the a2:)ple snail 

 [Helix pomatia), which he had brought from Germany, making 

 some remarks on its manner of feeding; and its habits while in a 

 state of confinement. 



PAPER READ. 



By Mr. F. G. Binuie.— ''On the Study of Land and Fresh- Water 

 Mollusks." In introducing his subject, the author defined the 

 work and scope of all true scientific study to be a strict investiga- 

 tion — exhaustive in its character — of the particular objects chosen 

 by the student, having for its ultimate end the deduction of broad 

 genei'alisations from these data, and the acquisition of accurate 

 views of the origin, plan, and laws of nature. After describing 

 the zoological position of the group now under consideration, and 

 its leading divisions, the author proceeded to the more special 

 consideration of its study, and stated that of the three great 

 aspects into which all zoological study divides itself — Morphology, 

 Physiology, and Distribution — the first-named was that most 

 investigated in the group, and in the Mollusca generally ; Distribu- 

 tion coming next in order. Physiology being least studied. Glancing 

 at a few of the more salient features in the development, habits, 

 and distribution of Mollusks, he indicated the directions in 

 which investigation, by observation and by experiment, might be 

 made — dwelling chiefly on the egg ; the more or less complex 

 metamorphosis gone through after leaving it; the growth of the 

 animal and its shell; maturity, its signs, and their value; the 

 senses of sight, hearing, etc. — specially-directed experiments being 

 here greatly needed ; food, hibernation, and aestivation; enemies, 

 with the means of defence and pi'otection adopted ; concluding 

 with some observations on distribution, mentioning the paucity 

 and incompleteness of our knowledge as to the influence of soil, 

 climate, moisture, &c., with relation to individual habit, and the 

 several stages of development, in facilitating or retarding growth 

 and numerical increase ; also the various facilities and means of 



