170 THE CHICAGO ACADEMY OF SCIENCES. 
roughened by growth lines; interior white and pearly, exterio 
chestnut brown. 
Length, 7.00; breadth, 4.50; aperture, length, 6.00; breadth, 3.50 mill. (16652.) 
Animal: Limaciform, broad and rounded at the posterior 
end, tapering toward the anterior end; eye-peduncles cylin- 
drical, rather long, the eyes at their. tips; tentacles simple, 
short; mantle placed near the posterior end, very small; sur- 
face of body roughened by small folds and furrows; no pedal 
grooves present; color brownish on back and sides of body, 
light yellowish on base and sides of foot. 
Jaw: Wanting. 
Radula: 20-0-20; central tooth rudimentary or wanting; 
lateral teeth long and narrow, with a barbed point and a swell- 
Ya sat cy ES 
Fic. 28. 
Lateral tooth of TESTACELLA HALIOTOIDEA Fér. (Original.) 
ing on the center of the posterior side. There are about 50 
rows of teeth (Fig. 28). 
Distribution: Southern Europe; Great Britain and Amer- 
ica (introduced); Canary Islands. 
Geological distribution: Unknown. 
Habitat: So far as known this species has only been found 
in this country in greenhouses, where it has been introduced 
on plants. 
Remarks: Testacella is one of the few truly predaceous 
pulmonates. It is nocturnal in habit and feeds upon worms, 
other mollusks and even upon its own species. It will pursue 
an earthworm through its many subterranean burrows or gal- 
leries with a persistency that recalls the ferocity of the tiger. 
During the day the animal buries itself deep in the ground, 
and in winter it forms a cyst or cocoon by the exudation of 
mucus. It is common in Southern Europe and has been intro- 
duced into Great Britain, where it has multiplied very rapidly. 
At the present time it is known in this country in the green- 
houses at Nova Scotia, at Roxborough, Philadelphia, Penn., and 
one specimen has been found in the greenhouses at Lincoln 
Park, Chicago. It will probably be found in the greenhouses 
of other cities. 
