The caddis flies may be divided into two families, though the distinguishing marks are so minute that they really ought to be classified as one family only. To Mr. McLachlan we owe many thanks for his researches in this group of insects.
Fig. 52.—Hydropsyche Montana.
Fig. 53.—Marronema Rubiginosa.
Family 1, Inæguipalpia.—This family includes the largest species of the tribe, and are principally found in northern regions.
One of our largest British species is Phryganea grandis, which measures four-fifths of an inch in length, and over two inches in expanse of the wing. It is an abundant insect, of a brown colour, with yellow rings on its antennæ, and the anterior wings are ash-coloured, clothed with brown.
The larvæ of this group for the most part inhabit quiet waters, ponds, canals, etc.
This family is subdivided into three sub-families, viz., Phryganeidæ, Limnophilidæ, Sericostomidæ.