EVOLUTION 135 
glance is remarkably like Barnea (Pholadida), 
and occurs in similar situations (Plate XXXII., 
Figs. 15 and 16). 
The reproduction of lost parts takes place to a 
considerable extent among the Mollusca. Experi- 
ments made in the eighteenth century by Spallanzani, 
and fully confirmed later by Tarenne, go to show that 
Snails can reproduce not only the tentacles, but even 
at times the whole head, while Madame Power 
obtained similar results so far as portions of the foot, 
mantle, and tentacles of marine species were con- 
cerned. The cerata of Nudibranchs it is known can 
be reproduced, as well as the arms of Cuttlefish and 
the siphons of Ensis and Solecurvtus. In some cases 
self-amputation can be voluntarily performed and 
the parts rts reproduced. This is the case with the 
swimming lobes of Lobiger, the hind-portion of the 
foot of Harpa, and the long mantle fringes of Lima. 
These last will live for some hours after separation 
from the animal. The phenomenon has also been 
observed among Land Snails. Thus in Cuba, 
Gundlach has recorded that Pleurodonta imperator 
and P. crassilabris part with the hind-portion of the 
foot, which will show signs of animation fifty-four 
hours after, the line of separation always occurring 
at the same spot, and the lost part being soon re- 
produced. The West Indian Stenopus is credited 
with a like faculty. In the Philippines, Semper 
