at the apex (Figure 136); these tubercles are the clinging organ of the pupa 

 with which it anchors itself; this enables it to make rhythmic movements 

 driving the water through the tube; the function of the dorsal processes of 

 the 1st abdominal segment of the pupa is thus analogous to that of the dorsal 

 and lateral papillae of the 1st abdominal segment of the larva. The dorsal 

 process of Phryganeidae (Figure 136, A) is a high tubercle with apical 

 spines; in the Limnophilidae, it is a saddle-shaped tubercle (Figure 136, B); 

 in the Leptoceridae, it forms small tubercles at the posterior angles of the 

 segment (Figure 136, C); in the Lepidostomatidae it forms two tubercles at 

 the sides of the segment (Figure 136, D). Small spines or points are present 

 at the apex of the processes. 



[91) 



4sl 



4gp 



/*** * A l 



138 



FIGURES 137 and 138. Clinging apparatus of the abdomen of the pupa: 



137 — Annulipalpia: Hydropsyche nevae, presegmental and postsegmental 

 sclerites of segment 3 (A); Macronema radiatum, presegmental sclerites 

 of segments 3 and 4 and part of the postsegmental plate of segment 3 (B); 



138 — Integripalpia (after Thienemann): Agrypnia pagetana (A); Lepto- 

 cerus senilis (B). 



83 



