108 
TEE \CONCHOLOGISTS®: 
EXCHANGE. 
ored body, and the mantle when extended 
forms a triangular plow in front of the shell. 
A breathing tube rises up between the mantle 
lobes, and when the little fellow is left undis- 
turbed he quickly plows his way just under the 
surface of the sand, keeping up a communica. 
tion with the water above through this eleyat- 
ed trunk, 
Here is another shell, one that I found 
clinging to the rocks, down where the breakers 
came in wild andhigh. It is shaped like the 
bowl of a large spoon. ‘The outside is rough 
and brown, and moreover it seems to have 
been selected as a building site by several tiny 
creatures which unhappily perished at the 
same time that our mollusk lost his vitality. 
But the inside of the shell is rich and dark 
and glossy, and as you look at the long mus- 
cle-scar you seem to see a big ow] solemnly 
perched in this snug retreat. The shell is 
named Lottia gigantea, Gray, but, besides its 
mere name and nature, it tells me a_ story of 
the hidden beauties of the sea. 
There are two elements of our being which 
the study of nature is fitted to develop. One 
is the intellect, to which pure science appeals, 
and which calmly and critically examines, de- 
cides upon and then appropriates the truth as 
its proper food. The other element is our 
emotional nature, which rejoices in every re- 
velation of beauty and which links pleasing 
associations to every natural object in which 
are found evidences of taste and wisdom and 
skill. Happy is the young student who learns 
to unite the two, who never sacrifices truth for 
sentiment, but whose life grows richer and 
happier as he gathers and appropriates the 
wonderful facts of science. 
Lxychanaes. 
FREE TO SUBSCRIBERS. 
Terms to NON-SUBSCRIBERS, which must be 
cash with order, are as follows: Exchanges of 20 
words, including address, 10 cents; for each addi- 
tional 10 words the charge will be 5 cents. No ex- 
change will be inserted for less than 10 cents. 
Offered.—300 species land, fresh-water and marine 
shells in exchange for others. Correspond in Vola- 
puk where possible. A. A. HINKLEY, DuBois, Il. 
Will exchange a fine set of Agassiz Con. Nat. 
Hist., 4 vols., 4to cloth, for old historieal works. S. 
W. HUMPHREY, Dedham, Mass. 
A collection of minerals, 50 varieties, for | a collec- 
tion of stamps, coins or Indian relics. All letters 
answered. WILL. P. ARNOLD, Shannock, R. I. 
Offered.—Unio lens, subrostratus, sopus, dona- 
ciformis, metanevrus, ellipsis, pustulatus, alatus. 
Marg. complanata, marginata rugosa. Anodonta 
fragilis, parvona, piana, grandis (said by Mr. W. A. 
Marsh to be very fine and nearly typical.) Pleuro- 
cera undulatum, troostii, florenceensis. Sph. trun- 
catum. Lists exchanged. A printed list of Hen- 
dricks county shells will be sent on application. C. 
A. HARGRAVE, Danville, Ind. 
arboreus, Say;  viridulus, 
Menke; limatulus, Ward; fulous, Drap; minuscu- 
lus, Binn; Patula strigosa, Gld.; striatella, Anth.; 
Helicodiscus lineatus, Say ; Ferussacia subcylindrica, 
L.; Pupa muscorum, L.; blandi, Morse; fallax, Say ; 
armifera, Say; Vertigo simplex, Gld.; Strobila laby- 
rinthica, Say; Stenotrema monodon, Rack.; leaii, 
Ward; Mesodon multilineata, Say ; clausa, Say; 
Vallonia pulchella, Mull.; Suwecinea avara, Say ; 
verilli, Bland; obliqua, Say, (all other Suecinea) ; 
Limnea eaperata, Say; humilis, Say; desidiosa, Say: 
all other Limnca resembling these; all Leptolimnea; 
Helicina occulta, Say. Specimens are desired from 
as many localities as possible. Jn all cases a careful 
description of the habitat of each set of specimens is de- 
sired. Wand, fresh-water, and marine shells are 
offered in exchange. List sent on application. Vi- 
viparide, Strepomatide, Pupade, and Corbiculade 
are also wanted. B. SHIMEK, Iowa City, fa. 
WANTED.— Zoniles 
Offered.—Unio alatus, Say, plicatus, Leseuer, fra- 
gosus, Con., trigonus, Lea, Maryaritana complanata, 
Say, and many others, for marine shells. JOSEPH 
ANDERSON, Box 1955, Muskegon, Mich. 
Oftered.—70 species of inland and 50 of 1 marine 
shells for other shelis, Send your list for ours, 
JOHN M. HOLZINGER, Winona, Minn. 
American, especially Califor nian, and “European 
shells to exchange for books and papers on botany, 
conchology, etc., “for other specimens. G. R. LUMS- 
DEN, 54 N. Second St., Norwich, Conn. 
Rare Volutes, Cypreeas, Olivas, Cones and Ss. Ameri i- 
can Shells wanted. 500 duplicates offered for them. 
THE CoNCHOLOGISTS’ EXCHANGE, Chestnut Hill, 
Philadelphia. 
Wanted.—Scarce Postage Stamps. 
Offered.—100 varieties of shells, named and local- 
ized. T. R. SWIFT, Chestnut Hill, Philadelphia, 
Offered.—Land and fresh water shells from this 
locality for other shells. Have about 300 of Unio 
cylindricus, Say; tuberculatus, Barnes; gibbosus, 
Barnes; rectus, Lam; alatus, Say; verrucosus, 
Barnes; pressus, Lea; zig-zag, Lea; elegans, Lea; 
gracilis, Barnes; metanevrus, Rat,; soleniformis, 
Lea; complanatus, Barnes; cornutus, Barnes, 
JAMES H. FERRIS, Joliet, Ll. 
