120 M. Hilgendorf on Spongilla nitens 
the ‘ Vega’ expedition, I venture to propose the name in- 
signis for this grand species. I believe it is larger than any 
other known Pleurotoma, recent or fossil. It is about three 
inches long and an inch broad. Colour creamy under the 
coating of a Hydrozoon which infests all the specimens. 
Whorls 7-8, convex ; apex turreted. Sculpture consisting of 
numerous spiral striz or slight ridges, besides a rather sharp 
and prominent keel in the middle of each whorl. Suture 
distinct. Fissure or slit broad but not very deep, placed 
about halfway between the suture and the median keel. The 
infrasutural or fissural space is marked (as in other species of 
Pleurotoma) with flexuous lines of growth. Mouth irregularly 
oblong. Many of the specimens have a short sinus in the 
outer lip at the commencement of the canal, which latter is of 
moderate length and nearly equally wide throughout. Inner 
lip smooth, and polished by the continual attrition of the foot. 
Operculum none. ‘There were ten living specimens in this 
collection. CEPHALOPODA: Heteroteuthis tenera, Verrill, 15 
fathoms. 
After all has been said we cannot be much surprised to 
find that this Exhibition is not a museum of natural history. 
The masses are as yet far from being educated in such 
matters, and they would simply regard a properly arranged 
collection of specimens which are not useful to man in the 
most cursory and incurious manner and without the slightest 
scientific interest. Perhaps it may be different in the next 
century. 
XVII.— On two Freshwater Sponges (Spongilla nitens, Carter, 
and 8. Bohmii, sp. n.) collected by Dr. R. Bohm in the 
River Ugalla near Lake Tanganyika. By M. HILeEn- 
DORE*. 
THE fifteen dry specimens, of bright greyish-brown colour, 
from 5 to 15 centim. [2 to 6 inches ] in diameter, and of broadly 
conical, hemispherical, or horizontally expanded form, closely 
resemble one another. Their surface is covered with short 
slender prominences, each separated from the neighbouring 
ones by interspaces larger than its own diameter and con- 
tinued radially through the interior substance of the sponge. 
In the principal portion a framework goes from one radial 
cord to another; and in the meshes thus formed numerous 
* Translated from a separate impression from the ‘ Sitzungsbericht 
der Gesellschaft naturforschender Freunde,’ May 22, 1883, communicated 
by H. J. Carter, F.R.S. &c. 
~ a erg 
sae 
