new Mollusks from South or Central Africa. 87 
A very similar shell to H. thelodonta, differing in being 
composed of more whorls, namely seven, as against six, 
greater attenuation of build, and feebler development of lip, 
though the various plice are arranged as those of the above- 
mentioned species. It is never difficult, however, to distin- 
guish them. 
XIV.—Descriptions of Seventeen new Terrestrial Mollusks 
Jrom South or Central Africa, in the Collection of Edgar L. 
Layard, Esq. By James Cosmo MELVILL, M.A., F.L.S., 
and JOHN Henry Ponsonsy, F.Z.8. 
[Plates IV.-VI.] 
THE seventeen species which form the subject of the present 
paper are from the collection of Mr. Edgar L. Layard, who 
has most kindly placed them at our disposal for description. 
1. Nanina hypochlora, sp.n. (PI. IV. fig. 8.) 
NV. testa imperforata, effusa, pallide stramineo-cornea, vitrea, levi, 
nitida; anfractibus quinque, planato-depressis, ultimo rapide 
accrescente ; apertura ovata ; peristomate simplici, tenui. 
Long. 4°50, lat. 12 mill. 
Hab. Cape of Good Hope (Edgar L. Layard). 
A plain, smooth, shining, and delicate little species, some- 
what flattened, the last whorl much the largest, lip thin, 
aperture ovate. 
Though of simple character it does not appear to have been 
previously noticed or described. Two specimens, precisely 
similar, 
2. Helix (Pella) rhysodes, sp.n. (PI. 1V. fig. 2.) 
H. testa profunde sed anguste umbilicata, tenui, depresso-convexa, 
corneo-fuscescente, ad apicem planato-depressa ; anfractibus 
quinque, apud suturas compressis, undique longitudinaliter liris 
albulis irregularibus oblique cinctis, ultimo anfractu ad medium 
yvix angulato; apertura lunari-ovata; peristomate simplici, tenui, 
ad marginem columellarem reflexo, 
Long. 4, lat. 6 mill. 
Hab. “8. Africa” (#. L. Layard). 
Unfortunately Mr. Layard has no record of the precise 
