CADDIS-FLIES 275 



Welshman's button, is altogether a darker fly. Mc- 



Lachlan says : " The living 

 Notidobia ciliaris. insect is entirely very deep 



black (with a slight steel-blue 

 reflection) excepting the legs, the posterior tibiae and 

 tarsi being yellowish or testaceous, the anterior and 

 intermediate less decidedly so, more dusky ; but the 

 expanded posterior wings are paler and more trans- 

 parent than the anterior. After death the colour 

 becomes gradually less intensely black (more 

 brownish)." The female may frequently be observed 

 carrying a yellowish mass of eggs at the extremity of 

 the abdomen, and these eggs, when deposited in the 

 water, open out into two thick flat plates, joined by 

 an intervening thickened ridge. 



The spur formula of the two succeeding genera — 

 Go'era and Silo — is for both sexes 2, 4, 4. 



Goera pilosa. The palpi of the male are very 



striking. Like those of 

 Goera pilosa. S. personatum they are very 



closely pressed against the 

 front, and scarcely distinguishable in a state of rest ; 

 they are three-jointed, the two basal joints very short, 

 and the third large, apparently subcylindrical and 

 curved. If the living insect is pressed between the 

 fingers these palpi become greatly elongated. It is then 

 seen that there is an apical portion which is ordinarily 

 concealed in the cavity and the basal portion is attenu- 

 ate and curved at the extremity, and that the whole 

 inner surface is covered with small blackish tubercles. 



