1-22 
MONSTROSITIES — COMBINATION SHELLS. 
the animal 
its "rowtli. 
may pennanently attach them together on continuing 
M. Barthehny, director of tlie hlarseilles Miiseung once 
found a Helix asperm which 
had evidently become lodged 
by some means within the 
empty shell of a Linuava 
st(((jn<ilh before attaiidng its 
full growth, and which in 
its progress to maturity, 
attached its own shell by the 
new growth to the shell of the 
Limnaa. 
Mr. Madison, of Birming- 
ham, has been very successful 
a number of 
Figs. 273, 274 . — Helix aspersa Miill., 
Collccled by M. I’arllicliny 
(after S. Petit), 
Showing the conjunction of two diverse shells. 
had the oppor- 
Fui. 273 . — Helix asperaa Miill., 
Reared by Mr. J. Madison, 
Showing a Darcelona nut iticor- 
porated with its shell by the inollusk. 
b 
ill obtaining 
these grotescpie sbells. Through his kiiuluess 1 have 
tiinity of e.xaniining many of the results 
of his patience and ingenuity. Some of 
the Helix axpersa — with which species he 
has mainly experimented — hehas induced 
to incorporate with their shells, in the 
process of their growth, full grown shells 
of Helix c(ii/ti((iia and other species in 
various odd positions; he has also con- 
trived to join with the growing shell of 
the inollusk more or less complete nut-shells and other objects. His 
series of these curious monstrosities is interesting and remarkable. 
In the Woodw'ardian Museum, Cambridge, there is a similar 
monstrons specimen from ITverston, possibly naturally grown, in 
wbich two shells of Helix aspersa have grown together in this way. 
iM. Cailliaud lias described the method of producing the union of 
these diverse .shells to be by breaking away the palatal or outer 
margin of the shell of an Helix aspersd, or any other species that 
may be selected for the operation, and then introducing the living 
inollusk into the empty shell which it is desired should be incorporated 
with or joined to its own, attaching the two together for a few days only 
by the aid of thread or other suitable inean.s, the inollusk usually 
ill that time has cemented the two shells together by the new growth 
it has been stimulated to make by the removal of portions of its shell. 
