306 Messrs. J. C. Melvill and R. Standen on 
multum impressis, pulcherrime regulariter decussatis, ad junc- 
turas lirarum spiralium cum costulis fimbriolatis, ultimo anfractu 
paullum prolongato ; apertura obliquiovata, labro effuso ; colu- 
mella paullum incrassata, simplici. 
Long. 7, lat. 1°75 mm. 
Hab. Gulf of Oman, lat. 24° 58’ N., long. 56° 54! E., 
156 fathoms. 
Rarely has a small mollusk caused such perplexity as in 
the present instance. Two examples alone have occurred, 
but both have the apex perfect, this being non-heterostrophe, 
though in most other particulars the form and texture recall 
such pyramidelloid genera as Mormula, Pyrqulina, or Mu- 
miola, especially one species of the latter genus—W/. sprrata, 
A. Ad.—which also occurs in the same seas. 
Mr. Edgar Smith considers Onoba egregia, A. Ad. (which 
should be removed from that genus), the nearest approach to 
our shell, and suggests that it might, at all events provi- 
sionally, be located in Aclis. In lip-characters it assimilates 
this genns, while resembling in the decussating sculpture a 
Cirsotrema, e. g. dentiscalpium, Wats. But perhaps the 
subgenus Constantia of Scala is best fitted for its reception, 
for it seems comparable with C. Standenz, Melv.*, also from 
the Gulf of Oman, in more than one point. 
Nassa (Alectryon) himeroessat, sp.n. (Pl. XXII. fig. 7.) 
N. testa minuta, ovata, albo-vitrea, delicata, apud basim et szepe ad 
suturas pallide stramineo-suffusa, vel zonata; anfractibus 6-7, 
quorum 32 apicales leves, vitrei, spiraliter unicarinati, ceteris 
apud suturas gradatulis, longitudinaliter arcte levicostatis, inter- 
stitiis undique tenuiliratis; apertura fere rotunda, intus alba, 
labro incrassato, intus spiraliter striato; columella paullum ex- 
cavata, canali brevissimo. 
Long. 5, lat, 2 mm. 
Hab. Gulf of Oman, at several dredging-stations in lat. 23° 
to 25° N., long. 57° to 59° KE. 
Depth ranging from 7-156 fathoms. 
We at first confounded this species with N. babylonica, 
Watson, and most probably the latter does not occur in the 
Persian Gulf region. The present species is locally very 
abundant, and the fine smooth ribs, small size, subpellucid 
substance, and less graduate whorls will serve to distin- 
guish it. 
Tritonidea Sowerbyana, sp.n. (Pl. XXII. fig. 8.) 
T. testa ovato-fusiformi, solidula, epidermide setulosa tenuiter con- 
* Ann. & Mag. Nat. Hist. ser. 7, vol. iv. pp. 92, 98, pl. i, fig. 11. 
+ ipepdes, pleasing, 
