9 
north latitude. Also that Bruce found it at the same place in 
Palestine, and in two lakes of Abyssinia. 
As the plant bears a heavy head upon a lofty stem, and does 
not root strongly in the ground, it can never have been common 
in Egypt, for the high winds and strong current of the river 
would be too powerful for it. It was probably brought to 
Egypt chiefly from Nubia, and only grew in the marshes and 
back-waters of the river when within the true limits of Egypt. 
The communication concluded with a few remarks upon the 
technical characters of the plants derived chiefly from Parlatori’s 
paper in the Memoitres of the Institute of France. 
Proressor Liverne exhibited an echinoderm from the coral- 
line crag of Aldborough, which he referred to the genus Rhyn- 
copygus (D’Orbigny). Two imperfect specimens of the same 
species from the red crag have been figured and described by 
Forbes, who referred them doubtfully to the genus Kehinar- 
achnius, but these specimens evidently did not shew the peri- 
stome. 
Professor Liveing’s specimen is a depressed urchin, con- 
vex above, concave below, the concavity shovel-shaped, the 
posterior lobes being more developed and descending to a greater 
distance below the mouth than the anterior lobes. The apex 
sub-central, somewhat anterior, dorsal ambulacra sub-petaloid, 
the poriferous zones nearly parallel, extending nearly to the 
margin and open. The mouth (which in the specimen is partly 
crushed and one side gone) sub-central but somewhat anterior, 
the ambulacra about the mouth sharply defined, leaf-like, shallow 
_ depressions, with crenate margins, the interambulacral spaces 
"terminating in small tubercles. The anal opening marginal, 
transverse and overhung by a projection of the back. Genital 
pores somewhat large and three in number, the left anterior 
pore wanting. The whole test covered with thick-set tubercles, 
