68 
Tom Tkkdale. 
The dead slud! is whitish with a faint brownish peripheral narrow' band. The 
apex is almost smooth, lint sliow’s slig’ht radial striae, the adnlt sculpture is 
faint radial growth lines, somewhat irregular in strength. Breadth 23 mm.; 
height 17.5 mm. 
Compared W’ith this species has a much more conical spire, more 
flattened wdiorls and lac'ks the columellar tubercle while the umbilicus is 
comiiletoly s('aled, there is not the slightest chink show’ing. 
Collected on tlu' Drvsdale River, Xapier Broome Bay, North-West 
Australia. 
(ieims TENTJIGADA gen. iiov. 
Type T. percita s]>. iiov. 
Main' thin shells are labelled “In rocks. Limestone Caves, Napier Range,” 
and these do not correlate with any of the named groups. Shell thin, helicoid, 
a little conical, undiilicate, whorls rounded, sutures shallow, last whorl rather 
bulky, mouth descending, a little oblique, subcircular, the outer lip thin, 
reflected, the columella slanting, broadly reflected across and hiding the 
umbilicus but not appressed. 
Tlu'se shells have a different texture from the preceding Rhagadoid forms 
while the columella does not entf'r the umbilical cavity nor is it appi’essed but 
expands across the umbilical o))ening. The apex is finely radially striate, 
w'hereas generally in Rhagadoid shells the apical whorls are smooth. 
Tenuigada percita sp. nov. 
Plate V., tig. 14. 
Shell thin, transparent, subglobosc', spire somewdiat elate, conical, whorls 
rounded, sutures little impressed, last whorl with a faint periidieral keel at 
beginning, periphery well rounded finally, ouler lip a little <lescending. mouth 
roundish, opini, older li|) thin, reflected all round, the columella broadly 
angulalely relhaded over umbilicus which however is not closed by it. The 
apex is I'ather coarsely radiate", the- radials breaking up into gi'anuh'S, the 
sueeeeeling scnlpliii’e' being I'atlu'r e'oarse" greewtb radials, almost radial riblets. 
which becenne weaker with age wlien concentric striatioii aiipears, and this 
can also be seen eehsenrely ein the base. A callus e-onuccts the outer li]} and 
the colinnella. Cedoration pale brownish horn. Bre'udth 19 mm.; height 
14 mm. 
Collected in reecks at the' Idnu'stone' Caves, North End of Napier Range, 
by L)r. 41. Basedow'. 
Tenuigada ignara sp. nov. 
Plate- Ah. fig. 13. 
Colleete'd with the ))i’eceeling, but probably in a slighth^ different loca- 
tion, were maiiy smaller specimens of the same type, but there were paler in 
coloration, more elepre'sseel, the (eeripheral keel more noticeable, smaller, the 
mouth more descending, tlu' umbilicus com|)a7'nlively larger and more open. 
The apex is more strongly grannlose, the adult radial sculjiture w'eakci', the 
concentric striae scarcely discernible. Bi'eadth 16 mm. ; height 10.5 mm. 
Genus EXILIGADA gcii. nov. 
Type Exiligada negriensis sp. nov. 
Air. Richard Helms, in the yeai- 1896, collected a number of shells at 
Negri Outstation, twenty-five miles north of Ord River Station, East Kim- 
berley. Tw’o species wu'i'e procni'ed and they do not fall into any Rhagadoid 
