CADDIS-FLIES 277 



larger size. For angling purposes the two species 

 may be considered as one. 



The grannom {Brachycentrus subnubilus) has a 



spur formula for both sexes 

 Brachycentrus of 2, 3, 3. The name is 



subnubilus. derived from two Greek words 



(/S/oax^'y, short ; Kevrpov, a spur) 

 referring to the shortness of the two spurs on the 

 tibiae of each of the fore-legs as compared with those 

 on the medial and hind legs. The fly is well known 

 to many anglers, and the case of the larva is quad- 

 rangular, of vegetable matter, and is figured at Fig. 49. 

 The grannom is one of the earliest of the sedges, 

 appearing in extraordinary numbers about mid-April 

 on the rivers which it frequents. On the Kennet, 

 during a good hatch, the fly has been observed like a 

 grey mist across the river, and the water itself has 

 been covered from bank to bank with a scum of cast- 

 off" pupal shucks. 



Lepidostoma hirtum is an insect in some ways 



resembling the grannom, inas- 

 Lepidostoma hirtum. much as the ^<g^ sac is of a 



very similar blue-green colour. 

 It can be readily distinguished from the grannom, as 

 its spur formula is 2, 4, 4. It can also be separated 

 from others of this group and family by the presence 

 of black scales on the palpi and the basal joint of the 

 antennae of the male. The name is derived from 

 XeViy, -/^oy, a scale ; and a-r6/j.a, a mouth. It appears 

 generally about August, while the grannom is essen- 



