Zoological Society. 495 



16. AcHATiNA Deshayesi, Pfr. A. testd turrito-ovatdy tenuius- 

 culdy subl(Bvigatd, nitidd, corneo-fuscd ; spird elongatd, convexd, 

 apice ohtusuld; suturd simpUcey suhprofundd ; anfractihus 7 

 convexis, ultimo |- longitudinis suhcBqudntey basi rotundato ; 

 columelld subtortd, late et oblique truncatd ; aperturd vix 

 obliqud, rhomb eo-semiovali ; peristomate simplice, obtuso, mar- 

 gine dextro subrepando. 



Long. 11, diam. .5 mill. 

 Hab. in insula Ceylon. 



17. AcHATiNA CEREA, Pfr. A. tsstd oblongo-turHtdy tenui, sub- 

 mit er et regulariter striatd, nitidd, pelluciddy pallide cered ; 

 spird recfilineari, apice obtusd ; suturd mediocri, minute crenu- 

 latd ; anfractibus 8 vix convexis^ ultimo ^ longitudinis vix su- 

 perante, infra medium subangulato ; columelld curvatdy abrupth 

 truncatd; aperturd obliqud, oblongd ; peristomate simplice, 

 recto, margine dextro leviter arcuato. 



Long. 14, diam. 4f mill. 

 Hab. Fernando Po (Fraser). 



18. Helicina subl^vigata, Pfr. H. testd conoideo-depressd, 

 soliduld, sublcevigatdy nitiduld, unicolore rubelld vel albidd, 

 subtus violaceo zonatd ; spird breviter conoided, vertice obtusulo; 

 anfractibus 5 vix convexiusculis, ultimo latiore, peripherid ob- 

 solete angulato ; aperturd diagonali, subsemiovali ; columelld 

 brevi, simplice, callum crassiusculum, circumscriptum retrorsum 

 emittente ; peristomate simplice, breviter expanso, margine 

 basalifere rectilineari, ad columellas subdentato. Operculum 

 tenue, corneum. 



Diam. maj. 8, min. 6^ alt. 5 mill. 

 Hab. in Novis Hebridibus. 



Notes on the Didunculus, a species of Pigeon supposed 



TO BE PECULIAR TO THE NavTGATOr's IsLANDS. By LiEUT. 



THE Hon. F. Walpole, R.N. Communicated by J. H. 



Gurney, Esq., F.Z.S. 



May 25. , 

 Lieut. Walpole always saw this bird (when in its natural state) 

 either perching on trees or flying about them, — feeding by day and 

 roosting by night among the branches. He never saw them on the 

 ground, though he has seen places where they appeared to have been 

 scratching, either for roots or for other food. The crops of the spe- 

 cimens which he examined were, however, generally filled with green 

 berries, which grew in clusters on a species of ash. The number of 

 specimens so examined was considerable, as the birds formed Lieut. 

 Walpole' 8 principal food while on these islands. He found the flesh 

 most excellent, though in colour darker even that of the English 

 wood-pigeon. The flight of the Didunculus is mostly limited to a 

 transit from wood to wood, as they rarely attempt to pass from one 

 island to another, — the distance between the islands varying from ten 

 to eighty nautical miles. 



