294 
POPULAK SCIENCE EEYIEW. 
of the larvae of seven out of the eight genera which, according 
to that author, constitute the family of Phryganeidce : — 
a 
<D 
<D CO 
fO O 
\ 
With a 
circular / 
opening 'i 
Thoracic 
segments 
rounded 
External organs of respiration . 
isolated, legs moderate > ° 
External organs ) ^ } Mystacida 
of respiration ^ ° 
Ditto, short . Sericostoma 
in bundles 
Thoracic segments with the front angles 
^ pointed 
Opening with a slit 
The pupa enclosed in a double envelope . 
Trichostoma 
. Hydroptila 
. Rhyacophila 
Larvae not 
enclosed in a 
movable case j The pupa enclosed in a single envelope . , Hydropsyche 
Mystacida^' (Latr.), maxillary palpi very long and very 
pubescent, with five joints in both sexes ; antennae longer than 
the wings ; anterior wings straight and elongated, with a few 
transverse nervures ; posterior folded ; antennae setaceous. 
Trichostoma (Pictet), maxillary palpi three-jointed in the 
male ; the terminal joint club-shaped and clothed with hair ; 
antennae with basal joint hairy; anterior wings without trans- 
verse nervures, clothed with short thick hairs ; posterior wings 
small and moderately folded. 
Sericostoma X (Latr.), maxillary palpi of the male dilated 
in the form of a spoon, uniting to form a rounded muzzle; 
antennae large, with basal joint long and thick ; anterior wings 
without transverse nervures ; posterior small, and slightly 
folded. 
Rhyacophila § (Pictet), maxillary palpi short, slightly pu- 
bescent, with five joints' in both sexes, terminal joint ovoid, 
antennae moderately long, slender, anterior wings without 
transverse nervures ; posterior narrow, slightly folded ; abdomen 
frequently terminated by horny appendages. 
Hydropsche || (Pictet), maxillary palpi with five joints in both 
sexes, the last long, filiform, often equalling the four others; 
antennae as long as the wings, slender ; anterior wings without 
transverse nervures ; posterior wings much folded. 
* From the Greek jutWraf, moustache,” in allusion to the pubescent 
palpi. 
t From Qp\^, rpixoc, a hair,” and croficf, a mouth,” in allusion to the 
pubescent j oint of the maxillary palpi in the male. 
t From arjpLKoc, '^silken,” and aronaj ^^a mouth.” 
§ From pva^j ^^a stream,” and ‘^1 love.” 
II From Uiopj water,” and 4'^x^y, “ a butterfly.” 
