384 
MR. NEWPORT ON THE NERVOUS SYSTEM 
there are now eleven, [Plate XII. fig. 1. ( 1,2 to 1 1 ),] besides a nodulated mass in 
the head which is supposed to represent the brain, [fig. 1. (a), fig. 2. (a).] This 
mass lies above the oesophagus, and is formed of two lobules closely united, 
convex upon their upper, and a little concave on their under surface, so as in 
the middle line to accommodate themselves to the anterior part of the dorsal 
vessel, which passes immediately beneath them, and to the oesophagus along 
which this is directed. The longitudinal cords originate from the under sur¬ 
face of these lobules, [Plate XII. fig. 2. (g),] and passing a little backwards meet 
beneath the oesophagus, and, by their uniting, form the heart-shaped or first 
ganglion, [fig. 1. (1), fig. 2. (h, 1).] From this they are continued close to each 
other into the next segment, or true collar of the future moth, and here con¬ 
nected form the second ganglion, [fig. 1. (2),] which is nearly of a spherical 
form. The cords then gradually diverge, and proceed apart from each other, 
passing on the outside of, and inclosing between them the insertions of some of 
the diagonal muscles of the future thorax, until they again unite in a third and 
distinctly bilobate, heart-shaped ganglion, [fig. 1. (3).] From this they are 
continued in the same manner into the fourth segment, and uniting form a 
similarly-shaped fourth ganglion, [fig. 1. (4).] They then pass close to each 
other into the anterior part of the fifth segment, and form a ganglion, [fig. 1. (5),] 
the distance of which from the fourth, like that of the second from the first, is 
scarcely more than half of what exists between any of the other ganglia. From 
the fifth they are continued to the sixth, seventh, and so on to the eleventh 
segments, forming in the middle of each, one nearly spherical ganglion, [fig. 1. 
(5, 6, 7; 8, 9, 10,11),] which has scarcely any appearance of having originally 
been formed of two lobes. The eleventh ganglion, however, is distinctly bilo¬ 
bate, [Plate XII. fig. 1. (11),] and at this period of the larva's existence is in 
reality a double ganglion, with a constriction in its middle, which is more or 
less apparent in different individuals ; so that, as was suggested to me by 
Dr. R. E. Grant, it is highly probable this eleventh, or terminal ganglion, con¬ 
sisted originally of two separate ganglia, with short intervening cords. This is 
the more probable as there are no ganglia, or cords, in the twelfth and anal 
segments, the parts being supplied with nerves directly from the terminal 
ganglion. This opinion is also supported by the fact, that in the larva of 
several other moths, particularly that of the Phalcena ( Bombyx ) neustria, Linn., 
