196 LAND AND FRESHWATER 
to the reflected inner lip; peristome oblique, crenulated on the outer 
lower margin, with four notches, solid, double, and much reflected ; 
operculum multispiral, with a central dark depression. 
Size: major diam. 5:0, alt. axis 4:0 mm. 
x On20" “5 0-16 inch. 
This shell in its simple straight portion of the whorl at the con- 
striction shows a resemblance to the Asalu species figured by me in 
the J. A. 8. B. 1871, fig. 3, which I then thought a variety of A. 
ingrami; but it is quite distinct, and the Asalu species I now name 
A, bicrenatus. 
Genus Ruapnavtos, Pfr. 
(Plate XLVII.) 
Rhaphaulus, Pfr. in Novit. Conch. i. p. 75 (1856); Pfr. Mon. 
Pneum. vol. ii. p. 90 (1858); Stoliczka, J. A. S. B. 1870, p. 151 
(animal). 
Type &. chrysalis, Bens. A. M. N. H. 1856, vol. xvii. p. 342. 
Original description :—‘ Operculum tenuissimum, corneum, sub- 
angustispirum, extus concaviusculum. Testa umbilicata, pupine- 
formis; apertura circularis; perist. subduolza ; imternum continuum, 
externum dilaiatum ; ad wisertionem marginis dextri canali aperto 
perforatum, canali sutural interno profunde in caverna spire desi- 
nente, utringue pervio.” 
Pfeiffer had described this genus previously under the title of 
Anautus, taking as the type A. bombycinus, Pfr., from Sarawak, 
Borneo (P. Z. 8. 1855, p. 105); but he apparently did not retain it 
after creating the genus haphaulus. 
Benson afterwards founded the genus Srrepraurus (A. M. N. H. 
1857, vol. xix. p. 201), with S. blanfordi as type; it is thus 
described :—* Testa umbilicata, pupiniformis, nitens ; peristoma cir- 
culare, non continuum, superne tubulo suturali interno et externo, 
continuo, ad extremitates ambas aperto, siphonem mentiente, perfo- 
ratum. Opere. res 
As the animal does not differ from that of Rhaphaulus, and as the 
chief point of difference is confined to a single character, the posi- 
tion and form of the sutural tube at its terminal end, Streptaulus 
cannot be considered generically or even subgenerically distinct. The 
form of this tube is most variable, even in the species S. blanfordi ; 
in some, as var. tubulus or var. (3, it is upright, like that of A. chry- 
salis; in var. tortuosus y it is directed downwards as in RB. pachy- 
siphon and assamica. 
Mr. Benson (Ann. & Mag. N. H., August 1859, p. 94) has 
described the animal of the genus RAaphaulus and other genera from 
specimens sent home alive by Captain Haughton, then (in 1859) 
‘Magistrate of Moulmein, and by Captain Sankey :— 
“Foot oblong, rounded anteriorly, narrowed posteriorly, and 
rounded at the extremity; muzzle short, declivous, rounded at the 
front, not emarginate nor lobed; tentacula somewhat short, slightly 
ringed, pointed at the summits and then slightly tumid, colour a 
