DR. J. BRAXTON HICKS ON UNDESCR1BED SENSORY ORGANS IN INSECTS. 153 
dge 
Q. Formica rufa. 
1. Apical joint of palpus. 
2. End of maxilla. The nerves (a) are distributed to the numerous hairs on the 
Fi°\ R. Palpi of larva of Colymbetes striatus (Striped Water- Beetle). 
1. Maxillary palpus: a, internal maxillary palpus. 
2. Apex of labial palpi with papillae. 
3. Apex of maxillary palpus, with papilla at apex (b) ; the nerve supplying them is distinct (a) 
Fig. S. Palpi of Forficula auricularis. 
1. Last segment, with elevation in centre, supplied by the nerve (a). 
2. Enlarged view of section of elevation, having a papilla in centre [b). 
Fig. T. Tactile hairs on under surface of proboscis of Diptera. 
1. In Blow-fly. 
2. In Eristalis (Drone- fly). 
3. Enlarged view of latter. 
Fig. U. Tactile hairs in Ixodes Dugesii, on the fifth joint of the tarsus. 
Fig. V. Barrel-organs of Lepidoptera. 
1. In Argynnis Paphia. A side- and end-view. 
2. Enlarged view, showing nerve (a). 
3. In Vanessa Atalanta. 
4. Enlarged view, showing nerve (a a). 
5. In Mormo Maura. 
6. Transverse section, showing position of wings. 
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