British Species of Caddis-flies. 75 
until I see the males I cannot speak with certainty.* Mr. Eaton 
has also taken females near Blandford, which may likewise belong 
here. 
It is not a settled question, whether this be truly Kolenati’s 
species; several closely allied forms are found on the Continent 
which are readily separable by the appendices of the males, but 
descriptions in which these parts are omitted are almost useless. 
One (unnamed) species is found both in the North of Europe and 
in North America. 
Fam. SERICOSTOMID. 
Antenne about as long as or shorter than the wings, generally 
rather stout, the first joint usually longer than the head, strongly 
hairy, the succeeding joints short; ocelli absent; maxillary palpi 
in the males two- or three-jointed, usually broad, hairy, and curved 
up over the face, varying very much in form in the different 
genera; in the females five-jointed, rather hairy, the basal joints 
thicker than the others, terminal joints nearly cylindrical, straight ; 
anterior wings usually rather short and broad (excepting Serico- 
stoma), with a dense hairy clothing; neuration generally indistinct 
unless the hairs are removed, varying much in the different genera 
and frequently differing in the sexes; discoidal cell generally 
closed; posterior wings broad, folded, rather shorter than the 
anterior ; legs not very long or strong, almost without spines, the 
anterior tibize always with two spurs, the number varying on the 
others. Abdomen short and sometimes rather stout. In the 
male the appendices vary much in the different genera, and are 
often of a complicated structure. 
Larva frequenting running waters: Head small and transverse. 
Pronotum and mesonotum rounded at the angles (Sericostomes, 
Pictet), or with the anterior angles greatly produced ( Trichostomes, 
Pictet). Abdomen with the sides nearly parallel; the processes 
on the second segment not strongly developed; respiratory 
filaments short and few in number. Legs short; anal crotchets 
very short. Pupa with the mandibles edentate. 
Case a cylindrical tube formed of sand, smaller at one end and 
tapering gradually (Sericostomes), or short, broad and flattened, 
with larger fragments of stones fixed on each side (Trichostomes), 
Comprises those genera in which the maxillary palpi of the 
* In August, 1865, I took upwards of thirty specimens at Arundel; all are 
females. I am now disposed to consider this form as distinct; it is darker, 
broader-winged, and more densely pubescent than 4. vestita. The capture of 
the male can alone decide the question. 
