Scientific Intelligence. — Zoology. 188 
and in some cases excited no little alarm. It may be added, 
that few specimens of the perfect moth have since been seen : it 
is therefore probable, that, owing to the occurrence of a good 
deal of wet weather in September, most of the larvae had pe- 
rished. 
35. An appearance seen on the Surface of the living Coral- 
lina officinalis . — When a small living branch of the corallina 
officinalis is placed under the microscope with sea-water, we ob- 
serve the rounded extremity of each of the last digitations tipt 
with a thin layer of a soft transparent colourless matter ; this 
transparent covering is spread completely over the free ends of 
all the branches, is thickest in the centre, and tapers gradually 
to the sides, where no trace of it is seen ; on the surface of this 
matter we can distinguish very minute tubercles or papillse, like- 
wise transparent, but which do not appear to have any motion. 
I have not observed this on any other part of the coralline ; and 
as it appears to have escaped notice, and may possibly have some 
connection with the mode of growth of a substance whose na- 
ture is still perfectly unknown, I have thought it worthy of being 
suggested to the attention of zoologists.. — Dr Grant . 
36. On the Spicula of the Spongilla friabilis , Lamarck. — In 
the forms and combinations of the ultimate spicula, in their ar- 
rangement into groups, and in the disposition of these groups 
around the pores, canals, and fecal orifices of the sponge, we ob- 
serve the same inexplicable uniformity of design in each of the 
different species, which is displayed in their outward forms, and 
in the disposition of their individual parts. This unity of plan 
is equally discernible in the structure of the Spongilla friabilis , 
which we have shewn in a separate memoir to bear the closest 
resemblance to that of the true sponge. There occurs but one 
form of spiculum in this species of spongilla ; it is simple, curved, 
cylindrical, and acutely pointed at both ends ; like most of the 
marine spicula, and the axes of many supposed keratophytes, it 
abounds with silica, and scratches glass, both in its natural and 
calcined state. Viewed through the microscope in its natural 
state it appears transparent, solid, and homogeneous throughout^ 
but on being kept for a minute or two at a red heat, it loses its 
transparency and symmetrical form : it becomes distended like a 
