122 



The Naturalist. 



paper was read by Mr. W. Harrison on ''Air, and Sources of Disease 

 from Impurities." — T. Lister. 



Beadfoed ISTatuealists' Society. — The first meeting of the year was 

 held Jan. 15th. The president, Dr. H. W. Evans, occupied the chair, 

 Mr. J. Saville described a recent ramble to the neighbourhood of Cot- 

 tingley, and exhibited several plants indicating the mildness of the 

 season ; Mr. B. lUingworth, a curious malformation of the hind foot of a 

 cow, in which the bones of the toes had all grown together. Mr. H. T. 

 Soppitt described several recent rambles, exhibited several early 

 plants in bloom, and reported having found a fungus, Coriinarius ileopo- 

 diui, new to the district, Mr. J. W. Carter exhibited several rare shells, 

 which were described by the president ; Mr. J. Firth, a number of 

 lepidoptera which pass the winter in the perfect state, which Avere 

 described and named by Mr. Carter. Dr. Evans then delivered his 

 inaugural address on " Conchology." He dwelt at considerable length on 

 the general organisation of the moUusca, pointing out their most curious 

 method of reproduction, the structure of the shell, and their mode of 

 locomotion. In dealing with their habits he showed how these animals 

 pass the winter by depositing at the mouth of the cell a kind of film to 

 keep out the cold, whilst in tropical countries many species pass through 

 the hot period by depositing a similar film and burrowing in the ground. 

 Dr. Evans then referred to the carnivorous habit of a marine species that 

 is found on the Yorkshire coast, which has a peculiar method of drilling 

 into the shells of other species and devouring the inmates. Almost all the 

 land and fresh-water species are herbivorous. One species (Testacella) 

 feeds on earth-worms. In size, the mollusca vary from extreme minute- 

 ness to veiy large and gigantic species. The largest land-shells are found 

 in South Africa, and belong to the genus A chatina, which is represented in 

 this country by an almost microscopic species. The address was listened 

 to with great interest, and a hearty vote of thanks was passed at its conclu- 

 sion. Mr. West showed a drawing of an abnormal mushroom in which a 

 second example was growing inverted out of a large specimen. 



Dewsbury Natubalists' Society. — January meeting, the new presi- 

 dent (Dr. Watts), delivered his inaugural address, thanking the members 

 for their courtesy in electing him. — He observed that, according to the 

 syllabus of the society, addressess were to be given during the year on 

 subjects connected with almost all branches of Natural History. Perhaps 

 he might be allowed to mention the study of insects as peculiarly interest- 

 ing, their various metamorphoses through egg, caterpillar, chrysalis, to 

 the imago or perfect insect. It was by a process of prolonged and careful 

 observation that physiologists had shown the various parasitic worms which 

 infest the bodies and alimentary tracts of man and beasts — the perfect 

 worm not being developed in the same species of animal as its progenitor, 

 going through three changes before it arrives at maturity, and is capable 

 of propagating its species. By this discovery physicians were enabled to 

 point out with certainty, that by subjecting animal food to a projDer heat 



