42 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 140 



EXPLANATION OF PLATES 

 Plate i 



The cephalic nervous system of Arcnophilus hipuncticeps (Wood) showing the 

 levels at which the sections seen in the following photomicrographs were taken. 



Inset, transverse section of the right antennal nerve showing the three nerve 

 bundles which innervate the intrinsic antermary musculature. The two ventral 

 bundles and one dorsolateral bundle are more heavily stained and enclosed in 

 their own neurilemma (not seen in silver preparations but verified in general 

 trichrome stains). 



Plate 2 



Fig. I. Transverse section through the antennal lobes, showing the fibers (flfi) 

 of the ventral bundle of nerves which innervate the intrinsic antennary mus- 

 culature. The large antennal glomerulus (glom) is ventrally situated. 



Fig. 2. Transverse section through the antennal lobes showing the fibers (ffa) 

 from the nucleus of origin of N9 (located immediately to the left of ffa). 

 PI[AL] is the pars intercerebralis of the fused antennal lobes. 



Fig. 3. Transverse section showing the lateral and medial lobes of the deuto- 

 cerebrum (Dl, Dm). The interior of the corpus lamellosum (elm) is weakly 

 stained but can be identified by its arrangement of parallel fibers. 



Plate 3 



Fig. I. Transverse section through the deutocerebral lobes showing the fibers 

 (ffa) from the cells in the pars intercerebralis (PI) entering the corpus 

 lamellosum (elm). 



Fig. 2. Transverse section showing the narrow band of fibers of the protocere- 

 bral bridge (PB) forming a commissure dorsal to the cerebral blood vessel 

 (CBV). The frontal lobe is dorsal and lateral to the deutocerebrum (D). 

 The stomatogastric ganglion, ventral to the cerebral blood vessel is damaged 

 and out of focus. 



Fig. 3. Section immediately following that illustrated in figure 2. The stomato- 

 gastric ganglion (STG) sends fibers into each of the cerebral hemispheres, 

 intercommunicating the two halves of the deutocerebrum. 



Plate 4 



Fig. I. Section through the large protocerebral commissure (LPC) showing 

 fibers {^i) intercommunicating the frontal lobes. Seen in cross section are 

 muscle fibers (mm) of the levator pharyngis immediately ventral to the 

 median recurrent nerve (Nu). 



Fig. 2. Section showing the recurrent nerve (Nu) flanked by the paired labral 

 nerves (N17). The arcuate fibers dorsal to the cerebral blood vessel are those 

 of the commissure of the circumesophageal connectives (COES). 



Fig. 3. Section showing the base of the brain and the circumesophageal con- 

 nectives (OEC). Note that the cellular cortex is beginning to envelop the 

 neuropile of the connectives dorsally, thus delimiting them from the caudal 

 portion of the supraesophageal ganglion. 



