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- 



FIG. 28. 

 Lateral tooth of TESTACELLA HALIOTOIDEA Fer. (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. 



