Mr. Garner on the Nervous System of Molluscous Animals, 497 
However, in other Cephalopoda, Loligo and Octopus, for instance, the two 
parts are not so distinct. In the midst of the nerves, which may be justly 
called the external nerves of respiration, arise the two acoustic nerves (/.) ; 
thus, as in vertebrated animals, connected at their origin with the nerves 
distributed to the respiratory tubes. The posterior portion is united to the 
anterior pedal portion, more or less intimately, in different genera. The aorta 
passes between them. "The nerves supplying the external organs of generation 
do not arise from the brain, as in Gasteropoda, from their widely different 
situation. "The pharyngeal ganglion (D.), quadrangular in Sepia, bilobed, as 
in Gasteropoda, in Loligo, is situated in its usual place, at the base of the 
tongue. Besides muscular and glandular branches (m.), it evidently sends 
down filaments (».) upon the cesophagus. The labial ganglion, which gives 
two nerves to the pharyngeal, is large and round; it sends fifteen or twenty 
filaments (o.) to the lips situated around the maxillz. As described above, it 
receives a nerve from the upper (sensitive), and another from the lower (motor) 
. portion of the circle. A filament runs across from it, over the upper surface 
of the superior lobe, towards a round tubercle of nervous matter (r.), situated 
upon the optic nerve*. The upper surface of the superior cerebral lobe pre- 
sents a division into an anterior and a posterior bilobed portion. As described 
above, it communicates by two chords on each side with the two divisions 
of the lower portion of the ring, the anterior band being in connexion with 
the band connecting the labial and pedal ganglia. The anterior division and 
band are larger in Octopus from the immense size of the feet-. The nervous 
purpose of preventing any disarrangement of the parts; and, lastly, a funnel or siphon, through which 
the current is evacuated, conveying away the excretions, without their gaining access to and injuring 
the viscera: with such an apparatus these animals can have no need of vibratile cilia, so common in 
Mollusca; and the author has convinced himself that they want them, by examining the excised 
gills of the adult, and also the living animal of the Sepiola and Sepia just escaped from the ovum. 
We see the use of so many respiratory nerves from the complication of these organs. 
* This little body has been figured in the Sepia by Mr. Owen (Anat. of the Pearly Nautilus). “It 
equally exists in Loligo and Sepiola. 
+ The Octopus creeps, as well as swims, by means of its feet; and these are the most general loco- 
motive organs in these animals. Some, however, as Sepiola, swim, by means of the contraction of the 
sac, in repeated jerks, the head being posterior, using the fins merely as rudders. The Sepia swims 
entirely by means of these latter organs, and consequently uninterruptedly ; commonly the head is 
posterior, but when it descends, it does so head foremost. 
VOL. XVII. 9T 
