ments, and likewise allied to the latter by the 
construction of their jointed locomotive legs ; 
these, however, instead of being only six in 
number, as in the true Insects, are, in the 
Myriapoda, always at least twelve, and fre- 
quently extremely numerous, being appended 
to all the segments of the elongated body, 
whence the names “ Centipedes” and “ Mille- 
pedes,” by which these creatures are commonly 
_ designated. All the members of the class are 
apterous ; they exhibit externally a succession 
of cylindrical or compressed rings, each of 
which sustains one or more, frequently two 
_ pairs of jointed feet, all of very similar con- 
_ Struction, being generally terminated by a 
‘single sharp claw. There is no consolidation of 
the anterior segments into a thorax resembling 
that of the Insecta, although many celebrated 
- Entomologists are disposed to regard the three 
"anterior rings as the representatives of the tho- 
racic segments. Upon the head are placed 
‘two antenne or feelers, which, in one large 
‘group, are short, stunted, and composed of 
“seven articulations, whilst in others these organs 
are long and setaceous, presenting a much 
greater number of distinct joints. Compound 
or simple eyes, allied in their structure to those 
of Insects, are generally, but not always, pre- 
Sent. The mouth is formidable, and, in many 
ts, resembles that of Insects, being fur- 
ed with strong mandibles, adapted to de- 
ir either animal or vegetable substances. 
the species breathe air by means of lateral 
mata and tracheal tubes, a circumstance 
reby they are at once distinguishable from 
Crustacea. Their jointed legs remove 
m from the Annevipa, while they differ 
from the Insecta in many important particulars, 
pat more especially in the progressive growth 
f their bodies, by the production of new seg- 
nts, and the development of additional loco- 
“motive limbs, the number of which increases 
With the age of the animal, while, on the con- 
‘y, in Insects, the segments that existed at 
h are found to coalesce into a smaller 
mber, and the prolegs of the larve become 
iterated when the Insect attains its complete 
hexapod condition. 
aa 
All the Myriapoda are terrestrial in their 
_ habits, lurking beneath stones or in the crevices 
of houses. Many of them inhabit decaying 
_ timber, or are found beneath the bark of trees, 
Ss they devour such vegetable substances 
_ as are adapted to their support; or, in the 
_ ease of the more highly organized species, 
_ Wage war against other animals, upon which 
t 1 aaa : . : 
e classification of the Myriapoda has hi- 
_ therto been and still is exceedingly imperfect 
_ and unsatisfactory, apparently in consequence 
of their very wide distribution and the general 
similarity of their appearance. Our country- 
man, Dr. Leach, in his zoological miscel- 
lany, was one of the first who gave a general 
arrangement of these animals, which was 
o by Latreille; but he appears only 
to have examined the European species. In 
Griffiths’ Translation of Cuvier’s Animal King- 
_ dom, Mr. J. E. Gray, of the British Museum, 
VOL. III. 
MYRIAPODA. 
545 
gave the figures of some exotic genera; but of 
these the Editor left the descriptions very im- 
perfect, and only made slight references to 
them in the explanations of the plates. Since 
that time Dr. J. F. Brandt published a mono- 
graph of the Myriapoda chilognatha,* in 
which he pointed out several new genera and 
re-named many, previously established by Mr. 
Gray. More recently M. P. Gervais has pub- 
lished his studies on Myriapods,+ consisting 
of a revision of the class and a list of the 
species, but having overlooked the slight notes 
given of Mr. Gray’s genera, has in one or two 
instances been led into error. Under these 
circumstances it is, with very great satisfaction, 
that we are able, by the permission of Mr. 
Gray, who has kindly placed his manuscript 
at our disposal, to lay before our readers the 
following review of the entire class. 
Order I. CHILOGNATHA, Latr. 
* (Julus, Linn.) 
Antenne seven jointed; rings of the body fur- 
nished with two pairs of legs. 
Fam.1. Juxip. Body cylindrical, smooth, 
rolling up into a spiral form and composed 
of many joints. Each segment formed of 
three imbricated parts, the upper part co- 
vering the body and sides of the abdomen. 
Antenne short, thick. Eyes many in a 
group. 
Gen.1. Jutus. ( Fig. 304, 1, 2, 3.) 
2d, 3d, 4th, and 5th joint of antenna elon- 
gated, attenuated; 2d longest, 5th and 6th 
longer than the rest. 
Fig. 304. 
Julus. 
* Bull. Soc. Imp. Moscow. 
+ Annales des Sciences Naturelles for 1837. 
2Nn 
