ters may prove to be accidental, ami not specific. It- rib-, which 

 arc very slightly worn, have Inn- ami there a subnndulous aspect : 

 upon the whole it approaches the typical sipho (which I regard a- 



perfectly distinct from exiffud), hut is i conic, with the ribs much 



more elevated, and with very distinct interstitial colouring. 



S. i:\ri.i m. S. testa parva, sol iff a, ovali-rotundata, pyrami- 

 datosubdepressa, ntbeymmetriea, niffro-cteruletcente, cottis 

 multis cinereis partis obtttsis plerumque alternatu hand confer- 

 tim radiata : oertice centraU, kevi, nigro-fuscescente, rimplici, 

 obtusiusculo : la/at' riphonifero aliquantulum majore : margine 

 subintegro : pagina interna picea, ad apicem pallidiore, vel 

 aubalbida, ad marginem albido breviesime radiata. 

 Long. 7 lin., hit. (3 lin. 

 Utih. Norfolk Island. Mus. Ilanley. 



Very distinct from any species known to inc. In the example 

 described there are about forty unarmed ribs, of which a dozen 

 upon the hinder two-thirds of the shell are peculiarly prominent, and 

 spring immediately from the erect vertex. There are indication- of 

 an epidermis, and of faint and crowded concentric Btriolae. 



S. uedimiculum, var. S. testa parva, tenui, ovato-oblonga, 

 arcuatosubconica, fusco albidogue zonula ; costis elevatis, mu- 

 ticis, snljcequalibus, rotundatis, aubdistanter radiata ,• lateribiu 

 valde inagualibtu : vertice valde excentrico, postico, in juniori- 



bus ad-unco : costa siphonifera inconspicua : pagina tola interna 

 fusco-pnrpurascenlc 

 Long. Ga lin., lat. 4f lin. 



Hab. ? Mus. Hanley. 



The comparative smoothness and almost uniform external colour- 

 ing of the previously described form of this remarkable-looking -hell 

 have rendered it desirable to redescribe the species. No interstitial 

 sculpture is present ; the ribs scarcely exceed twenty in number. 



5. A Monograph of the Genus Nyctoimiilus. 

 By Robert F. Tomes. 



The characters of the present genus were first briefly given l>\ 

 Dr. Leach in a communication to the Linnean Society in March 

 L820, which was not, however, published until L822. 



The paper is intituled, "The characters of seven genera of Bats 

 with foliaceous appendages to the nose;" the -e\ei genera being 

 Artibeue, Monophyllue, Mormoope, NyctophUue, Hfegaderma, I'um- 

 pyrus, and Madateua. 



From the manmr in which NyctophiltU i- here associated with 

 the other genera, it -eeins not unfair to assume that Dr. Leach re- 

 garded it as more or less closely affined to them : and they, with the 

 exception perhaps of Mormoopt, all appertain to the Phyllottm 



M . Temminck, in his monograph "i the genua, gives it as his 

 opinion that it may properly be placed between BAinolopkuM ami 



