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HELIX (EPIPRAGMOPHORA) KELLETTI, FORBES, 

 AND ITS HABITAT. 



By Mrs. M. BURTON WILLIAMSON, 

 Los Angeles, Cal., U.S.A. 



The usual habitat of North American land molluscs is in moist, shady 

 places under layers of fallen leaves, dead trunks of trees, or under 

 stones ; but in Southern California, where forests are rare, they must 

 be sought for in other places. The time to obtain the best results in 

 collecting is in the winter after the annual rain has set in, not in the 

 summer time as in the North Eastern States. In little canons on the 

 south side of low foot hills under loose rocks a few EpiprcujmopJiora 

 trasldi may occasionally be collected, these are more rarely found on 

 the under side of a cactus, but the former habitat is usually the home 

 of this species. There is, however, a species that is invariably found 

 on and under cacti; this species, E.liellettii, Forbes, is found on Santa 

 Catalina Island, a little island about twenty-three miles off the coast, 

 west of San Pedro Bay, California. The island is mountainous with 

 but little vegetation, and on some of the hills the prickly pear cactus 

 (Opuntia vtdgaris) grows wild ; here E. IceUettii may be found. 



The presence of these molluscs are heralded by the sight of a 

 chalk-white shell on the ground, or at the roots of the cactus partly 

 hidden from sight. Summer and winter the cactus bed is the home 

 of this mollusc, sometimes they may be found attached to the under 

 surface of dead branches or on the under side of green branches, 

 which is their favourite habitat in winter. Of all collecting probably 

 there is none that is so likely to keep down any tendency to enthu- 

 siasm as snail collecting in a bed of cacti. In the first place the 

 number of living specimens is limited; in the second place they are 

 difficult to capture, a stout stick being necessary in order to bring 

 the plant near enough — not an easy thing to do — to dislodge the 

 shell. This must be done with caution or even gloved hands feel 

 the effect ; then there must be constant alertness and caution or 

 shoes-and feet are pierced with the sharp prickles and bristles. 



How anything so soft and sensitive as the foot and body of a snail 

 can choose its home on the prickly pear cactus is a puzzle. Of course 

 the snail covers its passage with a slime that is a protection, but when 

 we consider that tufts of barbed bristles and long prickles run out in 

 every direction the Opuntia is not the kind of plant we would have 



