Cooke — Hazvaiian Zonitidae and Succineidae 271 



with a long indistinct inside cutting edge and a short distinct ectocone. The 

 inner marginals are distinctly bifid but without denticles on the outer mar- 

 gin. The very outermost marginals have about two minute denticles on 

 their outer margin. 



The finding of typical specimens of this holarctic genus in the 

 Hawaiian shell fauna is hard to explain. There can be no doubt 

 that they are endemic to the Territory of Hawaii and not of recent 

 introduction, as all the specimens that have been collected were 

 found at high altitudes (3000-8000 feet), and the possibility that 

 specimens were accidentally introduced in places remote from 

 human habitation is very slight. Furthermore the presence of 

 this species in the Pleistocene fossil deposits of Waikii, Hawaii, is 

 a strong argument against the theory of accidental introduction. 



NESOVITREA new genus 



Vitrea-like snails ; whorls about four, the first whorl smooth, the rest 

 minutely but distinctly striate. Aperture simple, outer margin thin, sharp. 

 Umbilicus rather shallow, perspective showing all the whorls. 



Contracted alcoholic specimens of the animals are without distinct 

 shell-lobes, but have a strong right dorsal lobe, an anterior left dorsal lobe 

 almost as well developed, and a long narrow posterior left dorsal lobe. 

 Lateral pedal grooves are well developed, but there is no indication of a 

 tail pore or slit in any of the much contracted animals examined. The 

 spermatheca is attached to the base of the uterus very close to the latter's 

 insertion on the cloaca. 



Type Vitrea pauxilUis Gld., from Maui. 



The name Nesovitrea is proposed for a small group of very 

 closely related species from the Territory of Hawaii. 



Besides the type this genus is made up of the following 

 species : 

 Vitrea (?) lanaiensis Sykes, Proc. Mai. Soc. London, ii, p. 298, 1897. 



Fauna Hawaiiensis, ii, PI. XL figs. 43, 44, 1900. 



■ Hawaiia Gude (Gude, G. K., Note on some preoccupied molluscan 

 generic names and proposed new genera of the family Zonitidae : Proc. 

 Mai. Soc. London ix, p. 272, 191 1 ) was originally based upon Helix kazvai- 

 ensis Pfr., and was said to equal Hyalina and Pseudohyalina in part. 

 H. kawaiensis had been referred to Pseudohyalina by Sykes (Fauna Haw., 

 ii, Moll., p. 279. 1900). Mr. Gude subsequently in an undated leaflet pro- 

 posed to change the type of Hawaiia to Helix Jiawaiieitsis Ancey ; but no 

 Helix lunvaiiensis was ever described by Ancey, nor was this specific name 

 ever used by him in Hyalina or Pseudohyalina. We are therefore compelled 

 to adhere to Mr. Gude's original designation of Helix kazvaieitsis Pfr. as the 

 type of Hawaiia. 



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