cee 
Subclass PULMONATA 
Order STYLOMMATOPHORA 
Division AULACOPODA 
Family ZONITIDAE 
This family of medium to small land snails is almost world-wide in its 
distribution and contains many species endemic to North America, The 
shell is usually umbilicate and has a low spire that gives it a rather dis- 
coidal outline. The lip is thin and not reflected. The animal has the 
margin of the foot defined by a pedal groove, which places the family in 
the Aulacopod group. Introduced species of importance belong to the 
genus Oxychilus and are generally found in and around greenhouses and 
cellars, and under rubbish or compost in gardens, 
Oxychilus alliarius (Miller) 
Shell small, smooth, highly polished, and amber or pale yellowish. Adults 
(with 4-5 whorls) measure 6-7 mm, indiameter. In living specimens the 
shell color is difficult to discern because the thin, semi-transparent 
nature of the shell allows the dark body of the animal to show through. The 
spire is hardly raised above the body whorl, giving the shell a rather dis- 
coidal appearance. The whorls are well-rounded at the periphery and are 
sculptured with fine, irregular growth lines. The sutures are moderately 
impressed, The umbilicus is about a millimeter in diameter and clearly 
shows the penultimate whorl. The aperture is ovate-lunate. 
Distribution; Central and western Europe, Iceland. Introduced in the 
United States and found in and around greenhouses in New York, New 
Jersey, Michigan, Colorado, and California. 
This snail and its two close relatives, O. draparnaldi and O, cellarius, 
are pests in greenhouses, and sometimes in gardens, where they are 
destructive to young and seedling plants. These snails are also predatory 
and carnivorous, feeding particularly on other snails. 
Oxychilus draparnaldi (Beck) (=Q. lucidus (Draparnaud)) 
Plate Il, 
This species is very similar to O, alliarius but adult shells with an equal 
number of whorls (that is, 4-5!) are more than twice as large (12-16mm.). 
The shell is strongly depressed and umbilicate, the umbilicus contained 
about 6 times in the diameter. Shell and animal coloration similar to 
Q, alliarius, Aperture ovate-lunate. 
Distribution: Europe, Orkney and Shetland Islands, Outer Hebrides, Asia, 
Minor, North Africa, Madeira, Introduced in the United States, chiefly 
