THE NAUTILUS. 



VOL. XIII. SEPTEMBER, 1899. No. 5. 



ANOTHER NEW ASHMUNELLA. 



BY II. A. I'lLSUUY AND T. D. A. OOCKERELL. 



Ashmunella thomsonlana porterse, n. var. 



Shell corneous, shining, with distinct lines of growth and minute 

 spiral incised lines ; umbilicus broadly exposing the penultimate 

 whorl; whorls 5^ to nearly G; lip ochreotis-tinged above and at the 

 edge, the teeth white; parietal tooth well-developed, outer tooth 

 long, basal tooth always bifid. Max. diam. 14-1G|- mm. 



Tentacles and dorsal surface of animal dark plumbeous; foot a 

 lighter brownish-grey ; exposed part of mantle grey. Genitalia as 

 in typical Aslimunella : penis with the thick basal part 4 mm. long, 

 the narrow terminal part (scarcely broader than the epiphallus) 

 3 mm.; epiphallus 28 mm. with the retractor muscle 3 mm. from its 

 beginning (thus higher up than in A. miorfiyssa) ; flagellum 1 mm.; 

 spermatheca filiform, 21 mm. long including duct. Eggs pellucid 

 white, 3 x 2 mm. 



Beulah (Upper Sapello Canon), New Mexico, 1899 : numerous 

 specimens collected by Miss VVilmatte Porter, after whom the variety 

 is named. Other specimen* later collected by Miss Helen Blake at 

 the same place. 



This form will fall into the first division of the t\vo keys to the 

 species of Ashmvndla given by the writers in Proceedings of the 

 Academy of Natural Sciences of Phila., 1899, p. 193.' 



1 " Ashmunella, a new genus of Helices, " by II. A. Pilsbry and T. D. A, 

 Cockerel!. 



