532 Proceedings of Scientific Societies. [May, 1885. 
(Lumbricus). Fifty-eight days after decapitation the worm had re- 
produced not only the brain, but the cesophageal collar and cesopha- 
geal ganglion. In one of the specimens exhibited, the lobes of 
the brain-mass were about one-half of the normal size; a secon 
had progressed further, while in a third the brain and ganglion 
were normal. The only perceptible difference between the re- 
generated ganglion and the original brain was a somewhat paler 
olor 
Feb. 1 7.—Miss Fielde stated that when twenty or more seg- 
ments, constituting the posterior portion of a worm, were cut off 
behind the clitellum, regeneration never took place at the cut 
end, but by the insertion of new pieces, Mr. Meehan accounted 
for the sparse distribution of the cedar of Lebanon by attributing 
it to the solidity of the cones, which never open, though the seeds 
are winged, and therefore designed for wide distribution. He be- 
lieved it probable that this close habit of the cones has only 
existed in comparatively recent times. The Indian species is so 
closely related that it probably sprang from the same ancestral 
stock. The only young trees which grow in a state of nature are 
produced from cones which rot in rock-crevices or are broken by 
accident. Professor Heilprin read a paper upon disputed points 
in geology and palzontology, with special reference to the greater 
adaptability of the lower forms of life to changed surroundings, 
and their consequent persistence in later geological deposits, as 
compared with the rapid extinction of higher types. Arguments 
were adduced in-favor of homoplassy in evolution or the origin 
of the same generic or even specific forms by distinct lines of 
ancestors, and the reappearance of extinct genera and species in 
subsequent geological epochs. 
eb. 26.—Mr. Potts described a new Hydrozoan from Tacony 
creek, This creature has a cylindrical body, surrounded at its 
free extremity by sixty or seventy papillz, but without tentacles. 
Very long ao are present. The usual length of the 
creature-is about ẹ of an inch. The ectoderm is an almost 
homogeneous hyaline substance filled with large cells. It was 
thought that a clear central space had been seen, and that a faint 
channel ending in a mouth could be traced. This appears to be 
the most primitive form of Hydrozoan yet described, its power 
of motion is very slight, and how it can capture prey without 
tentacles is a mystery. Mr. Potts suggested that it might be the 
larval state of a more developed form, as it had not changed, but 
had budded from the base. Professor Sharp argued in favor of 
t this organism, in common with other fresh-water 
organisms, y has degenerated from a somewhat higher type. Mr. 
_ Potts stated that he had received from Pictou Lake, Nova Scotia, 
is of the statoblasts of a new species of sponge. Speci- 
mens collected vain before Christmas indicated that it was an 
species. 
