MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 
115 
In Fig. 6 the microtome knife passed through the front region of the right olfactory lobe, 
involving the antennal nerve; in the succeeding section the olfactory lobes of both sides are 
involved, and the left antennal nerve in the five succeeding sections are represented in Figs. 8 
and !). 
Fig. 10 is an enlarged view of the section represented by Fig. 8. The cortical layer of 
ganglion cells supplying the taugied fibers composing the central myeloid substance is well devel¬ 
oped ; and here it should be observed that, as in Pseudotrcmia and the Ohilopod brains examined, 
the ganglion cells are very small and numerous, with a distinct central nucleus rather than scat¬ 
tered nucleoli. The fibers from the upper surface of the brain on each side of the median line 
are seen to form two bundles, passing towards the center of each procerebral lobe. The olfactory 
lobes are well developed, and on the left side the portions in the section were darker, more clouded, 
than the myeloid substance elsewhere. 
In this section were observed in the median line of the brain seven small areas, which remind 
one of the so-called central body of the insects. If these bodies, which are perhaps sections of 
bundles of fibers passing longitudinally through the middle of the brain, should provo to be 
homologous to the “central body” of insects, it will form an additional point of resemblance 
between the brains of Myriopods and the winged insects. But they need further examination and 
comparison with other out-of door Myriopods. 
THE ANATOMY OE THE BRAIN OE ANOPHTHALMUS TELLKAMPEII. 
(PL XXII, figs. 1-4, 4 a-if .) 
In order to understand the modifications in the brain of Anophthalmus due to a life in per¬ 
petual darkness we should compare it with the normal brain of another member of the same 
natural family, in which the eyes and brain are normal. It would be better, of course, if we could 
have examined that of a Trechus, but this has not been possible. PI. XXII, fig. 1, represents a dis¬ 
section of the head, with the eyes and brain, of a Carabid beetle, Ghlcenius pensylvanicus. Seen 
from above, after removing the integument and surrounding tissues and muscles, the brain of 
Chlmnius is, like the other members of its family and beetles in general, composed of two pro¬ 
cerebral lobes (pci.), with the well-developed antennal lobes in front, from which the antennal 
nerves (ant.) take their origin. On each side, between the brain (procerebrum) and eye, is situated 
the optic ganglion (op. g), which in Chiasmus is large and well developed, indeed only about a 
fourth smaller than a procerebral lobe. The eye is large and well developed. 
Comparing with Chlseuius the brain of Anophthalmus, it will be seen by a glance at PI. 
XXII, fig. 2, that there is a total absence of the optic ganglia and eyes. Traces of neither 
can be detected in gross dissections or numerous horizontal, transverse, and longitudinal sec¬ 
tions. It will be seen that the procerebral lobes are well developed, as well as the antennal 
lobes, an antennal nerve passing into each antenna. 
The general relations of the brain (supracesophageal ganglion) to the suboesophageal ganglion 
and other parts of the nervous system in the head are in part shown in PI. XXII, figs. 3 and 3 a, 
which represent a median longitudinal section of the head of Anophthalmus; pci. represents the 
brain or procerebrum, which is separated from the suboesophageal ganglion (see.) by the oesophagus 
(ce.). From the lower anterior aspect of the procerebrum passes a nerve to the frontal ganglion 
(/</.), and from it a nerve passes toward the labrum ( Ibr .). On the upper anterior aspect of the sub- 
oesophageal ganglion is what may be called the lingual ganglion, from which arises the lingual 
nerve (l. n.), which supplies the lingua (l). From a larger, more laterally and ventrally situated 
pair of lobes arise a nerve (mx. n.) giving origin to the (first and second) maxillary nerves. 
The horizontal microscopic sections represented by Figs. 4-4 c show that the optic ganglion, as 
well as the cornea, cones, rods, and retina, are all absent, with not even the rudiments left. Fig. 4/; 
represents the procerebral lobes, with the antennal lobes in front (ant. L), from which arise the 
antennal nerve (ant. n.). Fig. 4 d represents the two small lobes at the base of the antennal nerves, 
which have apparently been hitherto overlooked. 
Vertical sections of the brain are seen in Figs. 4e-4 g. In these and other sections of this 
beetle no traces of the so-called “ central body,” or mushroom body, with its calyces, have been 
