282 JOURNAL OF SCIENCE. 
Rhytida patula, n. s—Brown, yellowish at the apex, with 
numerous small longitudinal depressions and a few obsolete broad 
spiral grooves near the periphery. Teeth 18-0-18. Hab. Grey- 
mouth (R. Helms.) 
Rhytida citrina, n. s.—Translucent, pale yellow, irregularly 
indented. Teeth 17-0-17. Hab. Greymouth (R. Helms). 
Rhytida australis, n. s—Brown, darker in the umbilicus, irre- 
gularly indented, Teeth 16-0-16, Hab. Stewart Island (T. Kirk.) 
Testacella vagans, n. s. (Dandebardia novoseelandie, Trans. 
N.Z. Inst., XIV., p. 152, not of Pfeiffer)—Shell like that of 7. 
mauge?, but the dentition 15-0-15. Animal slate grey above, gra- 
dually passing into yellowish white on the sides. Hab. Auckland 
(T. F. Cheeseman). 
Leptopoma pannosa, n. s.—Small, conical, higher than broad, 
narrowly umbilicated, brown, covered with a dark fuscous, ragged 
epidermis, produced into triangular processes at the periphery, 
which is sub-carinated. Hab. Greymouth (R. Helms). 
Leptopoma calva, n. s.—Like the last, but more acute, not 
carinated, and the epidermis smooth. Hab. Greymouth(R. Helms). 
elses 19, 1882.—Professor J. von Haast in the chair. 
Specimens from the Weka Pass caves were pe by Pro- 
set Haast and Professor Hutton. 
. The discussion on Professor von Haast’s paper on the Weka 
are caves, read at the last meeting, was resumed by Professor 
Hutton, who said that in addition to the ocular evidence of the 
specimens on the table, the analysis made by Mr. Gray (see 
analysis attached) clearly proved that an external coating of car- 
bonate of lime must exist on the face of the rock. Iron carbonate 
was found both in the inner and outer portions, but was more 
abundant in the outer. This iron carbonate was derived from the 
decomposition of the glauconite in the rock, and as iron carbonate 
could not be precipitated from solution if oxygen was present (as 
iron peroxide must be formed), its presence in the outer portion of | 
the rock proved that the surface had been covered by an imper- 
meable layer. That this layer was carbonate of lime was also 
shown by the analysis, as that substance also was in excess in the 
outer portion. The analysis showed a slight excess, sufficient only 
for a very thin coating, but that was accounted for by the specimen 
analysed not being a typical one, it showed none of the paint, and 
the surface had evidently been abraded. If this incrustation had 
been formed by the water oozing out of the rock wall, the water 
must have carried out iron carbonate, and iron peroxide would 
have been precipitated. The analysis showed a complete absence 
of iron peroxide, and consequently the water, with the carbonate 
of lime in solution, could not have come out of the rock wall, but 
must have trickled over the surface from the roof; the wrinkled 
surface of the incrustation also showed that this was its origin. 
As for the name to be applied to the incrustation, Protessor Haast 
had said that it ought to have been called calc-sinter or stalactite. 
Professor Hutton quoted Dana’s ‘‘ System of Mineralogy ” (1874) 
as authority for applying the word stalagmite to calcareous in- 
crustations formed on the sides of caves by water trickling from 
the roof; stalactite was properly restricted to pendants hanging 
