NEUROPTERA. 75 
large, their antennz setaceous, and the maxillary palpi salient. 
Their wings are tectiform and but slightly reticulated or simply 
veined. They are extremely active and live under the bark of trees, 
in wood, &c. 
The following species is commonly found in EO and collections 
of Insects and plants. - 
P. pulsatorius; Termes pulsatorium, L.3; Scheff., Elem. 
Entom., cxxvi, 1, 2. Usually apterous; yellowish white; eyes 
and some small spots on the abdomen, russet. It was thought 
to produce that faint noise resembling the tick of a watch fre- 
quently heard in our houses, and of which we have spoken 
while on the genus Anobium—thence the origin of its specific 
name(1). 
5. The PrerurpEs, in which the tarsi are triarticulated, 
and the mandibles almost always partly membranous and small. 
The inferior wings are wider than the others, and doubled at 
their inner margin. 
They comprise the genus 
PeErRLA, Geoff. 
Their body is elongated, narrow and flattened; the head is tolerably 
large, the antennz are setaceous, and the maxillary palpi very salient. 
The first segment of their trunk is nearly square, and the wings are 
crossed and laid horizontally on the bodys; the abdomen terminates 
as usual by two articulated setx. 
Their larve are aquatic and inhabit sheaths or cases, which they 
construct in the manner of those formed by the Insects of the ensu- 
ing family, and in which they pass into the state of nymphs. They 
undergo their ultimate metamorphosis in the commencement of 
spring. 
Nemoura, Lat. 
The Nemourz differ from the Perlz proper in their very apparent 
labrum, corneous mandibles, the almost equal length of the joints 
(1) See Lat., Gen. Crust. et Insect., III, p. 207; Fab., Supp., Entom. Syst., and 
the Monograph of this genus in the Illust. Icon. des Insect., dec. I, of Coquebert. 
In the fourth volume of the Magasin der Entomologie of M. Germar, we find 
some anatomical observations on the common species—pulsatorius. 
