1903. ] MOLLUSCA OF THE “ SKEAT EXPEDITION.” 195 
The species of Zagochilus recorded from the Malay region are 
very puzzling and I think Dr. Moellendorff was quite right in 
describing as Z. rollei the form that I noted (under the name of 
L. townsendi) from Kelantan. The nearest ally of Z. kobelti 
appears to be LZ. townsendi Crosse; I have not seen an authentic 
specimen of that species, but have compared the form now described 
with the description and figures given by Crosse and with a 
specimen collected by Herr Grubauer, from whose collections 
Dr. Moellendorff has recorded Z. townsendi as the only species 
found. The shell I now name is a trifle smaller and more 
elevated in proportion to the breadth, and the umbilicus is 
narrower. It may be noted that the reference to Crosse’s original 
paper in the ‘ Journal de Conchyliologie’ should be to p. 200 and 
not p. 208 as given by De Morgan and Dr. Moellendorff in their 
papers on the Perak fauna. 
T have named the form after Dr. Kobelt as a trifling recognition 
of his recent study of the Cyclophoride. 
DITROPIS CAVERNS, sp. nov. (Plate XX. figs. 17-19.) 
Testa depresso-conoidea, late wmbilicata, olivacea, tenwis, glabra ; 
spira mediocriter elevata, apice eroso, sutura impressa ; 
anfr. 4 (2), convent, ultimus antice vin descendens, carinatus, 
carinis duabus supra peripheriam, unica ad peripheriam, et 
plurimis in regione umbilicali ; apertura subovalis, peristomate 
incrassatulo. Alt. 2°2; diam. max. 1:7 millim. 
Hab. In a eave, Biserat, Jalor. 
A single specimen only. 
CyCLOPHORUS MALAYANUS (Benson). 
Cyclostoma malayanum Benson, Ann. Nat. Hist. ser. 2, vol. x. 
p- 269. 
Hab. Gunong Inas, Perak. 
Recently when cataloguing (J. Malac. ix. p. 61) a collection of 
shells from Kelantan, I gave the names of Cyclophorus saturnus Pfr. 
and borneensis Mete.: both the forms then recorded have occurred 
in the present collection, and I have therefore again considered 
the identifications. Both, according to my present view, are 
erroneous, and the group is a very difficult one. The present 
species, which I regard as a form of C. malayanus, was then named 
C. saturnus, and the next species was called C. borneensis. 
CycLoPHORUS TUBA (Sby.). 
Cyclostoma tuba Sowerby, Proc. Zool. Soc. 1842, p. 83. 
Hab. Gunong Inas, Perak. 
See remarks under the last species; probably the C. borneensis, 
recorded by De Morgan from Perak, also belongs to this species. 
PYrEROCYCLOS SUBALATUS, sp. nov. (Plate XX. figs. 1, 2.) 
Testa late umbilicata, orbiculato-depressa, lineis increments notata, 
