36 THE NAUTILUS. 
Pror. H. E. SArcent has Jeft Woodville, Ala., to spend the sum- 
mer in Clearwater, Minnesota. 
Proressor THomas H. Hux .ey, the most famous of English 
biologists, died at 3.35 P.M., June 29, at the age of seventy years. 
Dr. W. D. Hartman, of West Chester, is publishing an Illustra- 
ted Catalogue of the Mollusks of Chester Co., Pa.,in The Village 
Record, West Chester. 
PLANORBIS SAMPSONI Ancey, described from Sedalia, Mo., and 
hitherto recorded from no other locality, is in the collection of the 
Acad. Nat. Sci., Phila., from Athens, Illinois, collected by E. Hall. 
PLANORBIS CENTERVILLENSIS Tryon.—This very distinct species 
seems to be quite widely diffused on the Pacific slope, but most west- 
ern collectors call it vermicularis Gld., judging from the labels of 
numerous lots before us. It is a small, brown shell, with high 
whorls, flat top, concave in the middle, and narrow umbilicus, while 
the true vermicularis is a flat, corneous shell, very similar to parvus 
or small deflectus, and doubtfully distinct from eastern forms. 
Mr. 8S. N. Ruoaps has returned from a collecting trip through 
Tennessee, from the Mississippi to Roan Mountain. Land shells, 
Unionide and Pleuroceratide were found abundant. Jo spinosa was 
rather scarce in the Tennessee, Nolachucky and Holston Rivers 
under boulders in swift water. Vitrinizonites was taken at Roan 
Mountain, as well as Polygyra andrewse aud major, with other fine 
and local species. Helicina occulta Say also turned up in east Ten- 
nessee. Mammals were scarce throughout the State, except at Roan 
Mountain. 
Mouuusks As PurRIFIERS OF WaATER.—Charles Hedley, in the 
Journal of Malacology, says: “A use, novel to me, of pond snails by 
the Chinese silk-growers, is described in an official work which 
caught my eye by chance. This waif of malacological information 
is so certain to escape recorders that I transcribe the passage: ‘ The 
water used for reeling silk is taken from mountain streams, as being 
the cleanest ; the water from wells is never used, and if mountain 
water cannot be had, river water is taken, which is cleaned by put- 
ting a pint of live shell-fish to one jar of water. There is a special 
kind of shell-fish, called the pure-water shell-fish (probably Vivipara 
chinensis Gray), found everywhere in ponds, wells and creeks. 
They first of all sink to the bottom of the jar, and then by degrees 
make their way up its sides, consuming gradually all impurities in 
the water within half a day or so. After the clean water has been 
drawn from the jar, the shell-fish are cleansed and put to the same 
= 999 
duty again. 
