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128 REPORT—1858. 
On the Liability of Shells to Injury from the Growth of a Fungus. 
By the Rev. H. H. Hicerns. 
It has often been observed that shells kept for a considerable time in cabinets are 
apt to lose much of their original freshness and beauty of appearance. This kind 
of injury chiefly affects such specimens as have a bright enamelled surface, which at 
length becomes dull and less pleasant to the touch. Several suggestions have been 
made with reference to the probable cause of the change, which has often been at- 
tributed to the efflorescence of saline matter absorbed by the shell. But, so far asI 
have observed, the specimens most liable to injury from saline incrustation belong to 
genera in which the shells are without enamel, as Littorina, Turritella, &c., and many 
collectors are in the habit of steeping their specimens in fresh water for some days 
before placing them in their cabinets—a process which is said to be an effectual pre- 
servative from injury by saline efflorescence. Mr. Dennison, of Woolton, attributed 
the loss of lustre in enamelled shells to the ravages of a minute insect, but had not 
been able to detect the depredator. ‘‘ Many of the shells in my own cabinet suffered 
such serious injury during last winter that I was led to investigate the cause, 
which, indeed, became obvious enough by the use of a microscope. An ordinary 
lens showed the enamel of the shell to be beset with small bristly points, and when 
a portion of the surface was scraped off and submitted to a higher magnifying power, 
the forms of at least two species of Fungi became apparent, one resembling an or- 
dinary Mucor with a globose sporangium ; the other, and much more common form, 
exhibited both simple and moniliform filaments, with an abundance of minute spores, 
seemingly quite free. After having been carefully washed, the surface of the shell 
was found to be as if it were engraved in some places with stellular marks, in others 
with striz forming irregular reticulations, caused no doubt in each instance by the 
spreading mycelium of the fungus. It is scarcely necessary to add, that attacks of 
this nature need not be apprehended where shells are kept in a perfectly dry or well- 
ventilated place. A slight deposition of moisture does, however, frequently occur 
upon their surfaces whilst shells are undergoing examination, in which case it would 
be a safe precaution to allow them for awhile to remain exposed to the air before re- 
turning the drawer to the cabinet.” 
On some new and interesting Forms of British Zoophytes. 
By the Rev. T. Hincxs, B.A. 
A new species of Plumularia was characterized under the name of P. similis, closely 
allied to the P. echinulata of Peach. Two new species of Polyzoa were also described : 
one as Avenella dilatata ; the other, which exhibits a new generic type, as Arachnidia 
Hippothéoides, a delicate Ctenostomatous Polyzoon, curiously resembling in general 
appearance the well-known Hippothoa. Mr. Hincks also drew attention to the re- 
markable difference in the form of the male and female capsule in Halecium Beanii 
and 7. halecinum, and suggested the importance of inquiring how far this difference 
prevails amongst true Hydroida. 
On some Peculiar Forms of Spines found on two Species of the Spinigrade 
Starfishes. By C. W. Peacu. 
The author stated, that having discovered a long slit on the under spines of Ophio- 
coma neglecta?, he was induced to examine other species; and that on Ophiocoma 
rosula, in addition to those mentioned by Forbes, he found jaw-like ones on the under 
sides of the rays, armed with hooked teeth—much like one of the claws of a lobster 
—and likewise a hook on the tips of the lower straight spines, all directed towards 
the disk. Similar jaw-like spines occur on the arm of an Ophiocoma minuta sent by 
Dr. Dickie from the collection of the late Mr. Thompson of Belfast; and as the author 
found several specimens, in all stages of growth, at Wick, N.B., in every respect like 
the Irish one, he thinks that the latter is only the young of the former. From not 
finding these noticed by Forbes, or any other writer on Starfishes, he has thought it 
right to lay this before the Association. 
