Marshall—On the Anatomy of the Dragonfly. 787 
PLATE LXVIII. 
Fig. 1. Front view of head. X 8. 
Fig. 2. Side view of head. X 6. 
Fig. 3. Posterior view of part of the head showing gula, Gu. X 6. 
Fig. 4. A partly diagrammatic median sagittal section through the 
head and cervical region. X 10. Ap. 1 and Ap. 2 apodemes. Cv. 
cervical region. 
Fig. 5. View of a part of the opposed margins of clypeus and labrum., 
showing one of the two hinges, the right hand one. X 105. 
a — a, edge of labrum. b — b, edge of clypeus showing part of 
the curved chitinous rod on this side, t, tooth on edge of cly¬ 
peus. r, thickened chitin along outer edge of the cavity in 
labrum into which t fits. 
Fig. 6. Anterior view of the head with portions of the frons and of the 
clypeus removed; part of each eye cut away. The stippled 
part shows the partition separating the frontal from the clypeal 
cavity. X 8. Ap. 1 and Ap. 2 apodemes. M. lb. Elevator mus¬ 
cles of the labrum. M. ph. Muscle of pharynx. 
Fig. 7. Inner surface view of labrum, above, and of hypopharynx, 
below. Each part drawn and then joined in their natural posi¬ 
tion. X 40. Oes. Oesophagus, drawn only in part, not continued 
to its outlet. Ph. Position of teeth upon which labrum articulates 
(Fig. 5, t). C. Brush, (Fig. 8, c). Ph. pi. Pharyngeal plate (Figs. 
8 and 10, Ph. pi.). 
Fig. 8. Median sagittal section of labrum, Lb. and hypopharynx, Hyp. 
X 20. The buccal cavity, the pharynx and the beginning of the 
oesophagus are shown. M. ph. Pharyngeal muscle. M. ep. 
Epipharyngeal muscle. Ph. pi. Section of the pharyngeal plate 
across the entrance to the pharynx (Fig. 7, Ph. pi.). C. One of 
the brushes on the labrum (Fig. 7, c). 
Fig. 9. Dorsal view of the alimentary tract. X 3. Cv. Cervical re¬ 
gion. Between MI and HI the dark lines represent the position 
of the Malpighian tubules, these are not drawn in full but only 
their position of attachment to the intestine represented by 
these lines. 
Fig. 10. View of the pharyngeal plate. X 40. 
Fig. 11. Sagittal section showing portions of the buccal cavity, the 
oesophagus and the pharynx. X 150. Gl. Glandular tissue on 
dorsal wall of pharynx. 
Fig. 12. Section through the dorsal wall of the pharynx. X 1100. Gl. 
Glandular tissue. 
Fig. 13. Transverse section of the oesophagus in the cervical region. 
X 280. 
Fig. 14. View of inner surface of cuticular layer of the oesophagus 
showing the small blunt projections which occur on this and 
other parts of the fore-intestine. X 1100. 
Fig. 15. Transverse section of the oesophagus cut through the meso- 
thorax. X 280. 
