89 



August 26, 1845. 



William Horton Lloyd, Esq., in the Chair. 



" Remarks on the genus Achatinella, Swainson, and descriptions 

 of six new species from Mr. Cuming's coUection." By Dr. L. PfeifFer. 



Upon examining the long series of forms ^vhich occur in the vast 

 family of the Helicea, I have ascertained that there are several groups 

 which Nature herself seems to have characterized as genera, though 

 it would be very difficult to draw out such a generic definition as 

 would exclude all other nearly allied species. One of these natūrai 

 groups is the genus Achatinella, proposed by Swainson in Brandt's 

 Journal, 1828, which appears to be peculiar to the Sandwich Islands, 

 and has been united to the genus Bulimus by most recent authors, as 

 by myself in my ' Symbolae.' However, the greater the number of 

 species we become acquainted ■vvith, the more convenient it appears 

 to unite them together as a distinct genus. I may therefore be per- 

 mitted to gi ve a short account of the species now knovvn. 



1. Achatinella lugubhis (Turho), Chemn. Described by La- 

 marck under the name of Monodonta seminigra, and figured by 

 Swainson in the Zool. lUustr. under the name oi A. pica. Of 

 course the name of Chemnitz mušt be retained. 



2. Achatinella perversa, Swains. Synon. Helix decora, Fėr., 

 1. 155. f. 5 — 7 ; Bulimus decorus, Pfr. Symb. 



3. Achatinella acuta, Swains. Hel. spirizona, Fėr., t. 155. 

 f. 14, 15. 



4. Achatinella bulimoides, Swains. Hel. lorata, Fer., t. 155. 

 f. 9—11 ; BuL loratus, Pfr. Symb. 



5. Achatinella livida, Swains. Hel. vulpina, Fėr., t. 155. f. 1, 

 2 ; Bul. vulpinus, Pfr. Symb. 



6. Achatinella rosea, Swains. A very distinct species, to which 

 none of Fėrussac's figures may be referred. 



7. Achatinella pulcherrima, Swains. This species might 

 perhaps be considered as a dextrous variety of A. livida. 



8. Achatinella turritella (Hel.), Fėr., t. 155. f. 13 ; Bul. tur- 

 ritella, Pfr. Symb. 



9. Achatinella tristis (Hel.), Fėr. Mus. ; Bul. tristis, Pfr. Symb. 



10. Achatinella ventulus (Hel.), Fėr. Mus. ; Bul. ventulus, 

 Pfr. Symb. 



''11. Achatinella radiata, Pfr. Ach. testd ovatd, soliduld, leviter 

 striatd, nitidd, viridi et luteo radiatd, strigis intercurrentibus ni- 

 gricantibus į spird conicd, obtusiusculd ; sutiird marginatd ; an- 



