36 THE NAUTILUS. 



Having experimented successfully witli these " remedies," I can 

 assure satisfactory results. Of course trapping under pieces of 

 board placed here and there, turning the same occasionally and col- 

 lecting by hand, may be practised with more or less success. 



In England, in wet, cool seasons, slugs are particularly destruc- 

 tive to fields of young wheat ; there they work at night. Lime is 

 used to a great extent, and trapping under cabbage and other large 

 leaves is often resorted to. Soot is sometimes used in the wheat 

 h'elds in the same way as lime. 



Another foreign slug Limax (Amalia) hewstom '( A. gagatesf) 

 had become a nuisance in the grass plots of San Francisco twenty 

 years ago, and has presumably extended its territory over a larger 

 area by this time. Our large native slugs, Limax (Ariolimax), 

 columbianus Gld., and its near relative californicus Cp., inhabitants 

 of Central California, the first-named found also as far north as 

 British Columbia, appear to be free of the sins which have made the 

 foreign forms obnoxious. These two species are sometimes met 

 with of the length of six inches. Their dirty yellowish green color, 

 often blotched or spotted, is rather repulsive. It is not unlikely that 

 slugs may become a serious pest to the farmers in some parts of Cal- 

 ifornia at some future time, an unwelcome incident pertaining to the 

 development of irrigation. 



The sense of smell seems to be highly developed in L. maximus, 

 and probably in all of the slugs, and again, the sense or instinct of 

 direction. L. maximus is the only species that I have had an oppor- 

 tunity to observe in this connection. The slugs are " not popular 

 with the masses ;" and very good people call them " nasty things." 

 Los Angeles, Cal., June 13, 1904- 



NEW MOLLUSCAN GENERA FROM THE CARBONIFEROUS. By 

 George H. Girty (Proc. U. S. Nat. Mus. xxvii, 1904). Limipecten 

 is a new genus of Pectenidse based upon a Texan species, L. texanus 

 n. sp. Its relations with Aviculipecten and Acanthopecten are fully 

 discussed. Pleurophorella is a new group near AHerisma, type P. 

 papillosa, Young Co., Texas. Clavilites is a new genus of Denta- 

 liidae, annulate like Plagioglypta, but having a dorsal ridge over 

 which the ribs pass with a strong anterior bend. Type C. howar- 

 densis, from Kansas. Schuchertella n. gen. is a Brachiopod group 

 formerly called Orthothetes, but not Orthotetes of F. de Waldheim. 



