Potassium Hydroxide by Dicramira vinula. 411 
Explanation of Plates VIII. and IX. 
Plate YIII. 
Fig. 1. — Dorsal view of alimentary canal of pupa of D. vinula 
the day after pupation : ce, oesophagus ; a r, alkaline 
receptacle ; mes, mesenteron ; r, rectum. 
Fia. 2. — Alimentary canal of pupa one month after pupa- 
tion : ce, oesophagus ; a r, alkaline receptacle ; mes^ 
mesenteron ; r, rectum. 
Fig. 2a. — Side view of anterior part of same, enlarged : ce, 
oesophagus ; a r, alkaline receptacle ; mes^ mesenteron ; 
r, rectum. 
Fig. 3. — Alimentary canal of freshly emerged imago : d, tube 
leading from body cavity to rectum ; ce, oesophagus ; 
a r, alkaline receptacle ; mes, mesenteron ; r, rectum. 
Fig. 3a. — Side view from another specimen, four days after 
emergence : d, tube leading from body cavity to 
rectum ; ce, oesophagus ; a r, alkaline receptacle ; mes, 
mesenteron ; r, rectum. 
Fig. 4. — Internal surface of " shield" of D.furcula : ce p, portion 
of pupal oesophagus ; hJc, hooks for securing " shield " 
to head of imago ; hk', small pair of hooks. 
Fig. 5. — Dorsal view of anterior part of head of imago of D. 
furcula : a, antlia ; maxillary palp ; hkg, groove 
for hooks {hk, in Fig. 4) ; I p, labral prongs as mere 
stumps. 
Fig. 6. — Ventral view of same : hk'g, depressed area in which 
small hooks of shield are lodged. 
Fig. 7. — Dorsal view of anterior part of head of imago of D. 
bifida : a, antlia ; maxillary palp ; mn, mandible 
remnant ; hkg, groove for hooks. 
Fig. 8. — Dorsal view of head of pupa of B. callunce. 
