208 Wisconsin Academy of Sciences^ Arts^ and Letters. 
Plate VI 
Fig. 12. Longitudinal section of testis. X 465. 
d.b. The dark body. s. Spermatozoa, sg. Spermatogonia, sp. Spermatids^ 
Fig. 13. The male reproductive system from a ventral view. X 160. 
c.a. The copulatory apparatus, e.d. The ejaculatory duct. Pr.l, Pr.2, Pr.3. 
The first, second, and third pairs of chitinous structures of the copulatory 
apparatus, t. The testes, t.h. The terminal hooks of the copulatory ap¬ 
paratus. vd. The vas deferens, v. The seminal vesicle. 
Fig. 14. Composite drawing of the brain. Outline of head. X 250. . 
a.l. The antennal lobe. a.n. The antennal nerve, e. The eye. lb. The 
labrum. o.l. An ocellar lobe. op.l. The optic lobe. p.l. The posterior lobe. 
Fig. 15. Longitudinal section of the central nervous system. X 135. 
c.h. Hairs on the clypeus. e.o.c. The circum-oesophageal commissure, c. 
The cardiac valve, g.l., g.2., and g.3. The first, second and third thoracic 
ganglia, n. The abdominal nerve, o.s. The oesophageal sclerite. sb.g. The 
suboesophageal ganglion, s.g. The supra-oesophageal ganglion or brain, t. 
A portion of the tentorium. 
Fig. 16. A composite diagram of the tracheal system from a ventral view. 
X 160. 
a.b. The antennal branch, d.b. A dorsal abdominal branch, e.b. The branch 
to eye. h.t. The transverse connecting trunk of the head. l.t. The main 
longitudinal trunk of the abdomen, t.s.t. A thoracic stigmatal trunk, t.t. 
The transverse trunk of the thorax, v.b. A ventral branch, vs.b. A visceral 
branch. 
