98 MANUAL OF THE MOLLUSCA. 
The species found at the Cape, Algoa Bay, Natal, &c., are for 
the most part different—Potamides decollatus, Clionella sinuata, 
and an Assiminea inhabit brackish waters. 
TETERESS sooo sossaoseoose . 4 —. — 
ENELOR apapoosasoascousee 1 MSUMNCE, 57 cas oreeeos sce 1 Paludina .........- Sere = 
— EPL SA ersecssassees\orors act Neritina.:css5--ssee-eeee ef 
WARIEINS, maonanoeoonoso0cee 4 PN YSOPSIS!-peseseresceecs 1 — 
TELS EBS SS pcan eo eee 3D ANG YIUSzs.5..8essccete eee 1 Corbicula viiccsssesesees OE 
SUCCINEA .......c0000 wo (4 Planorbis ....... Beane 3 Cy Class ss-2--seseesnesene uf 
TELE  nanoatossascon0as 13 — PisiGiuml 2 -e-esesoeeere 1 
TEND) sqromscincsacoscon WVAGCINNMS (a. cessse-eaee ate WHI10 "ss. sssssosererescaine i 
ACH Ais aac sesss)eassseee 7 Oncidium ese ceeceese =e. Pridiviayercesssessseceses eee 
Cyclostoma weeresseore 6 AUricula ......s00s0. 3 OE 
5. YEMEN—MADAGASCAR. 
The 8. W. Highlands of Arabia (Yemen) form a distinct 
Botanical province isolated by rainless deserts to the north. 
The land snails consist of a few species of Helix and Bulimus, 
Cyclostoma lithidion, and 3 species of the section Otopoma, a 
group also found in Madagascar. ‘Two species are common to 
the island of Socotra (No. 30), which also has a species (of Pupa) 
common to Madagascar. bulimus quillaini, Cyclostoma gratum, 
modestum and Souleyeti are found on the island of Abd-el-Gouri. 
Very few land shells have been collected on the mainland of 
Eastern Africa, although it is a rainy region, and well wooded 
in the southern part; 5 species only are recorded from Moga- 
doxa and Ibu, belonging to the genera Helix, Bulimulus, Acha- 
tina, Pupa, and Otopoma. Onthe Island of Zanzibar are found 
Achatina Rodatzi and allisa, Cyclostoma Creplint and Zangue- 
barica ; Pupa cerea is common to Zanzibar and Madagascar. 
Madagascar itself is rich in land shells; Dr. Pfeiffer enume- 
rates—Helix 28 sp., Bulimus 6, Succinea 14, Pupa 1, Achatina 4 
(one of which, eximia, is allied to A. Colwmna, of W. Africa), 
and 32 Cyclostomide, chiefly of the section with spiral ridges — 
(Tropidophora), 3 of the division Otopoma. Cyclostoma carini- 
ferum and Cuvieri are found on the Island of Nosse Be; Helix 
guillaini on §. Maria l. Amongst the fresh-water shells are 
Melania amarula, Melanatria fluminea, and Neritina corona. 
The land shells of the Mascurene Islands are nearly all pecu- 
liar; we are indebted to Mr. W. H. Benson for most of the 
information existing in respect to them. 
Comoro Islands. 
Helix russeola and Achatina simpularia are found in Mayotte ; 
Cyclostoma pyrostoma in Mayotte and Madagascar. 
