274 WEST COAST SHELLS 



shel]. One morning a few years ago I was surprised 

 to find the marble sun-dial on the lawn all dotted 

 with little grouj)s of these microscopic snails. I gath- 

 ered a number, and soon afterwards they disappeared 

 as suddenly as they had come. I have never seen 

 them since, though I presume they still live among 

 the grass roots. Under the microscope the shell is 

 very pretty, having a moderately elevated spire of 

 four whorls, which are marked with fine cross ribs. 

 The umbilicus is large, and the shell when inverted 

 looks like a shallow bowl. The shell is dark horn- 

 colored, and is about a large as the head of an ordi- 

 nary pin. The variety pasadenac^ Pilsbry, is widely 

 umbilicated, and is without the spaced riblets, or has 

 them very slightl}^ indicated. Its diameter is two 

 millimeters. It was found in a garden at Pasadena, 

 and presumably it had gone there to admire the flow- 

 ers, even as my specimens had climbed the college 

 dial to find out the time ot day. 



Punctum randolphii^ Dall, Randolph's Dot-shell, 

 has a minute, reddish brown shell, with a dull silky 

 lustre. Its tour whorls are quite elevated, and the 

 umbilicus is small. It is very minute, having a 

 diameter ot less than 2 mm. It is found under leaves, 

 near the city of Seattle. 



Helix aspersa^ Mull., the Spotted Snail, is a Euro- 

 })ean species which was introduced into this country 

 many years ago. It seems to thrive about settle- 

 ments, quite unlike most of our native species, and in 

 some j)laces it has already become a source of much 

 annoyance, eating garden flowers and vegetables al- 

 together too freely. It is very easy to raise broods ot 



