120 THE NAUTILUS. 



Over 200 specimens of the new variety have been examined and its 

 novelty seems constant. Both rudentis and smithii represent 

 extremes of variation of a common type. It is named in lionor of 

 Professor Frank Smith, who collected the specimens. 



NOTES. 



PoLTGTRA CLARKii BRADLEYi n. var. Similar to typical clarkii, 

 but lacks the basal tooth. It has the base malleate but without 

 strong radial sculpture. 



Alt. 10.5, diam. 14 mm. 



Locality: Black Rock Mt., Rabun Co., Georgia. Type in the 

 collection of the Academy of Natural Sciences, no. 104800. Named 

 in honor of the collector. Dr. J. Chester Bradley. Figured on plate 

 VIII, to appear next month* E. G. Vanatta. 



Maine Pearls. — Fresh-water pearls are obtained in Maine, as 

 far as I know, exclusively from Margaritana margaritifera Linnd. 

 Eight or nine years ago this noble mollusk was abundant in the small 

 streams about my home at Buckfield, Maine; but its numbers have 

 since been regrettably thinned by the ravages of pearl-hunters. 

 Probably, however, it will not be exterminated, since some individ- 

 uals will remain in hidden and inaccessible situations. 



I have found pearls rather copiously while collecting large mature 

 shells for specimens ; but most of them were dull or leaden-colored. 

 The largest shells found exceeded six inches in length. 



I recently conversed with a carpenter of Turner, Maine, who has 

 hunted pearls in his spare time. He did not destroy the clams in- 

 discriminately, as is done by the more ignorant and reckless pearl- 

 hunters, but only opened those which indicated by some external 

 malformation the probable presence of a pearl. He said that many 

 of the clams lived buried completely below the surface. These were 

 imbedded in the sand at the bottom of the brook and covered by a 

 layer of mud of vegetable origin perhaps six inches thick. 



He found one very large and fine pearl, spherical, "about as big 

 as a marble," in a conspicuously deformed shell. This brought him 

 $400, and it may be presumed that the ultimate purchaser paid a 

 considerably larger sura for it. — John A. Allen. 



