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CAROLINE BURLING THOMPSON 



2. GENERAL ANATOMY 



Text figure 1, a diagram drawn from a semitransparent mount 

 of the whole head of the queen of Camponotus pennsylvanicus, 

 shows the following parts: (1) the supraesophageal ganglion, 

 above the esophagus, its first part, the protocerebrum, consist- 



Text fig. 1 The head of the queen of Camponotus pennsylvanicus. A71. 

 antennae; a.l., antennary lobes; an. w., antennary nerves; /r.g., frontal ganglion; 

 Ib.fr.n., labrofrontal nerve; Ib.n., labral nerve; lb., labrum;m.6., mus-'iroombody; 

 md., mandible; md.n., mandibular nerve; oe., oesophagus; o.l., optic lobe; oc, 

 ocellus; p.int., pars intercerebralis; p.l., protocerebral lobe; r.n., recurrent nerve; 

 sb.g., subesophageal ganglion. 



ing of the protocerebral lobes, p.L, which form the greater part 

 of the brain, the optic lobes, o.l., lateral extensions of the proto- 

 cerebral lobes and connected with the compound eyes by the 

 numerous bundles of optic nerve fibers, the three ocelli, oc, con- 

 nected bv the ocellar nerves, with the ocellar lobes within the 



