INSECTA. 
345 
In the eleventh or the Rhipiptera, there are six legs, two mem- 
branous Avings folded like a fan, and two crustaceous moveable 
bodies, resembling little elytra * *, situated at the anterior extremity of 
the thorax ; the organs of manducation are simple, setaceous jaAA's 
with two palpi. 
In the twelfth or the Diptera, there are six legs, two membranous 
extended wings, accompanied, in most of them, by two moveable 
bodies or halteres, placed behind them ; the organs of manducation 
are a sucker composed of a variable number of setae, inclosed in an 
inarticulated sheath, most frequently in the form of a proboscis 
terminated by two lips. 
ORDER I. 
MYRIAPODA f. 
The Myriapoda commonly called Centipedes, are the only animals 
of this class Avhich have more than six feet in their perfect state, and 
whose abdomen is not distinct from the trunk. Their body, destitute 
of wings, is composed of a (usually) numerous suite of annuli, 
most commonly equal, each of Avhich, a few of the first excepted, 
bears two pairs of feet mostly terminated by a single hook ; these 
annuli are either entire or divided into two demi-segments, each 
bearing a pair of those organs, and one of them only exhibiting tAVo 
stigmata :j;. 
The Myriapoda in general resemble little Serpents or Nereides, 
their feet being closely approximated to each other throughout the 
Avhole extent of the body. The form of these organs even extends 
to the parts of the mouth. The mandibles are bi-articulated and 
immediately folloAV'ed by a quadrifid piece in the form of a lip Avith 
articulated dhdsions, resembling little feet, Avhich, from its position, 
corresponds to the ligula of the Crustacea : next come tAA’o pairs of 
part of the abdomen, while in the latter and in the Diptera it is incorporated with 
the thorax. 
* Formed, as we presume, by pieces analogous to the epaulette or pterygoda 
of the Lepidoptera. 
-h The Mifosata, Fab. 
J The annuli of the body of Insects are usually proA'ided with two stigmata. If 
those of the Scolopendrae, particularly the larger species, those which have twenty- 
one pairs of feet, be thus considered, it will be found that they are alternately desti- 
tute of, and provided with, two stigmata, and that thus, compared with these latter 
animals, they are in fact but semi-annuli. Each complete segment will then have 
two pairs of feet, one of which is supernumerary, since, in other Insects, the annuli 
furnished with feet have but two. 
