484 
INSECTA. 
Figr. 42.— lulus, with the body coiled up, /IpatitiitP nf fppf 
and the front of the body unrolled, with UeSlltUte OI leei 
the antenna magnified. 
four principal divisions, tubercled at its superior edge, the two middle divisions being narrower and 
shorter, and situated at the upper extremity of another piece, serving as a common base ; the legs are 
very short, and always terminated hy a single claw ; four legs situated immediately beneath the pre- 
ceding piece of the form of the following, but placed nearer together at the base, with the basal joint 
proportionately longer, and the majority of the remainder attached, in double pairs, to each of the 
succeeding joints. The male organs are placed behind the seventh pair of legs, and those of the 
female behind the second pair. The spiracles are placed alternately above the base of the feet, and of 
a very small size. 
The Chilognatha crawl very slowly, or, as we may rather say, glide along, rolling themselves into a 
spire or bail. The first segment of the body, and in some also the 
second, is largest, and represents a corselet, or small shield. It is only 
at the fourth, fifth, or sixth segment in different species, that the dupli- 
cation of the legs commences ; the two or four first legs are entirely 
free to the base, or they do not adhere to their respective segments but 
by a middle or sternal line. The two or three terminal segments are 
We observe on each side of the body a series of pores, 
which had been regarded as spiracles, but which, according to M. Savi, 
are merely orifices for the discharge of an acid fluid of a disagreeable odour, which appears to serve 
for the defence of these animals ; the respiratory apertures, discovered by him, are placed upon this 
sternal piece of each segment, and communicate interiorly with a double series of pneumatic pouches, 
disposed in a chain throughout the whole length of the body, whence extend trachean branches which 
are extended upon the other organs. According to M. Strauss, these vesicular tracheae are not con- 
nected together by a principal trachea, as is customary. 
The form of individuals just hatched is like a kidney, perfectly smooth and without appendages ; 
eighteen days afterwards they undergo a first moult, when they assume the adult shape, but they have 
only twenty-two segments, and the total number of their legs is twenty-six pairs. M. Savi appears 
to contradict the assertion of De Geer, that the young have only three pairs of legs and eight rings 
in the young individuals; but is it certain that the moulting 
of which Savi speaks is really the first ? — or ought we not, 
on the contrary, to conclude that these young do not sud- 
denly pass from a state exhibiting no locomotive organs to 
one with so many as twenty-six pairs, or in other words, 
that there are intermediate changes, which have escaped 
the notice of M. Savi ? Do not the observations of the Fi^. 43 .— Transformations of lulus, from Oe Geer. 
Swedish Keaumur confirm these intermediate changes ? Be this as it may, the eighteen outer legs 
alone serve for locomotion. At the second moulting the animal exhibits thirty-six pairs, and at 
the third moult forty-three ; at this time the body consists of thirty segments. In the adult state the 
male has thirty-nine, and the female sixty-four ; two years afterwards they again moult, at which period 
the generative organs first appear. From their birth, which takes place in March, until November, 
when Savi ceased his observations, these changes of the skin took place nearly monthly. In the 
exuvite, even the membrane which lines the interior of the elementary canal and tracheae is to be 
jierceived, the organs of the mouth being the only parts wdiich M. Savi could not discover. 
(Osservazioni per servire alia storia di una specie di lulus communissima, Bologna, 1817 ; and another 
memoir upon lulus fcetidissima, published in 1819, noticed in t\\Q Bulletin of Ferussac, December, 1823), 
These insects feed upon decaying animal and vegetable matter, and they deposit a great number of 
eggs under ground. According to Linnaeus they form the single genus 
Lulus, Linn., — 
which we divide as follows : — 
Some have the body crustaceous, without appendages at the tip, and the antennae thickened towards 
the extremity. 
[Fam. 1. — Glomerid.®, Westw., or the Onisdformes of Latreille, in the Cours d' Entomologies 
Glomeris, Latr., resembles Wood-lice, being of an oval form, and rolling themselves into a ball ; the body 
convex above, concave beneath, with a row of small scales along each side of the body beneath, analogous to 
each of the lateral divisions of the Trilobites. They are only composed of twelve segments, exclusive of the 
