44 
ON THE VALUE OF GYPSUM IN AGRICULTURE. 
Tubularia indiviss, a current of particles 
was seen within its tube, which, in its com- 
bined and steady flow, resembled the circula- 
tion in plants of the genus chara. I'he 
general course of the stream was parallel to 
the slightly spiral lines of irregular spots on 
the tube. Between tlie stomach and the 
mouth a remaikable action was observed. 
The mouth became swollen by a flow into it 
frorn the stomach, which continued for about 
a minute. The contents of the mouth were 
then squeezed back into the stomach, and 
during this reflux the connecting orifice was 
seen distinctly open, and it continued so till 
the stomach became nearly empty. The 
orifice then closed gradually, preparatory 
to the effort of forcing the fluid back to the 
stomach. 'J’wo currents were continually 
going on both in the mouth and stomach, 
one flowing down the sides and an opposite 
one in the axis. 
These observations were made by a micros- 
cope which magnified 100 times, and drawings 
were taken by a camera lucida slid over the 
eye piece. 
In the Sertularia pluina Ellis, a current 
was observed flowing in the channel back- 
wards and forwards throuoh the main stem 
and lateral branches of a pluma, and might 
be compared to the running of sand in an 
hour glass, five ebbs and flows occupying 
J5j minutes. When the connexion of a 
plume with the root was interrupted by ben- 
ding its stem, the stream running down the 
middle was observed to continue its flow up 
one of the lower and stronger lateral branch- 
es, and then to return down that branch and 
up the main stem. The section of a stem made 
below the commencement of the side branches 
exhibited a small stream apparently follow- 
ed by viscid matter. Cavolini first observed 
this, but no subsequent writer has noticed 
it. In Sertularia vumila, an irregular mo- 
tion was noticed in the stomach and mouth, 
and likewise, but not distinctly, in S setacea, 
dichoma, and in species of Cainpanularia. 
In a small Ascidia occurring on the con- 
ferva elongata, circulation was observed 
through the transparent coat, the particles of 
the blood not exceeding •00025 inch in dia- 
meter. The blood enters the heart from the 
peduncle, the ventricle contracts in the mid- 
dle and drives the fluid into the branchial or- 
gan, and into a network of vessels over the 
stomach and intestines. After the circula- 
tion has gone on for a while, the pulsations 
become fainter and gradually cease when the 
current is reversed. A Polyclinum exhibited 
also internal motions. 
In Cellularia and Flustra none of the in- 
ternal currents which in the sertuleriae con- 
nect the different parts of the zoophyte were 
observed, nor was any circulation detected. 
Each animal is enclosed in its cell, and sends 
out its mouth and arms through a valve. A 
short sheath precedes them, from whence the 
arms rise straight together, and then open to 
a funnel-shaped figure of beautiful regularity, 
serving probably to draw food to the mouth 
by currents. Between the animals of these 
genera no line of distinction could be detected. 
From these physiological observations, correc- 
tions may be brought about of the arrangement 
of many species. The Cerialaria lendigera he 
removes from the CertnLaritc nniX the Angaina- 
ria angtdna from the Tubnlaricz to the Celia- 
Inr polypi. 
ON THE NERVOUS SYSTEM OF 
THE SPHYNX LIGUSTRI. 
Bv G. Newton, Esq. 
In the paper of Mr. Newport, a minute de- 
tail is given of the nervous system of the 
Sj)hynx ligmtri during the latter stages of its 
pupa and imago states, and on the means by 
which its developement is effected. During 
the passage of the insect from the larva to the 
pupa state, the gauglia and nervous cords un- 
dergo great changes both in their form and 
situation, and likewise in their number ; and 
after these changes have been carried to a cer- 
tain extent, they are suspended for several 
weeks, during which the insect hybernates. 
At the end of this period the changes again 
proceed. The insect remains in the pupa 
state about 43 weeks, and during this period 
the concentration of tlie nervous system pro- 
ceeds to a much greater extent. The author 
describes the double origin and connexions of 
the nerves distributed to the w'ings, the object 
of which appears to be, toestablish a harmony 
of action between the wings in those insects es- 
pecially, which are remarkable for velocity 
and power ofsight, a different structure being 
adopted in those which fly with less regularity 
or speed. 
A pueumogastric nerve or par vagum is de- 
scribed, which is distributed to the organs of 
digestion and respiration. The author like- 
wise notices lateral cephalic ganglia, which 
may be regarded as auxiliary brains, and a 
sympathetic nerve; besides a set of nerves 
which appear to correspond with the respira- 
tory nerves of vertebrated animals. The 
primary longitudinal nervous cords of insects 
are shown to consist of two tracts, the one 
situated over the other, corresponding to the 
two columnsofwhich thespinal cord consists 
in vertebrated animals ; the one forms the seat 
of sensation, and the other of motion. The 
same observation has also been made upon 
the lobster. Scorpion, ^nd Scolopendra, and in 
several insects, as the Gryllus viridissimiis, 
the Carabus, and Papiliourticae. 
Such are the principal papers of which 
this portion of the Philosophical Transactions 
consist. The substance of Mr. Powell’s 
paper, with additions, is inserted in a preced- 
ing part of this Journal. It is rather remark- 
able, that with the exception of a short notice 
of a mineral water, there is no purely chemi- 
cal paper contained in it.— Records of Gene- 
ral Science 1835, 
EMPLOYMENT OF GYPSUM IN 
AGllICULTURE. 
Gypsum has been employed in Switzer- 
land, Germany, England, and North America 
for many years as a manure, but it was only 
brought into use in France about forty years 
ago. At present it is very generally used in 
that country, with the exception of the de- 
partments of Gard and Herault, (Ann, des 
Mines, vi, 193.) 
