36 F. G. HBATHOOTB. 



Fig. 10. — Longitudinal section through a segment of the heart, art. 

 Artery, osi. Osteum. 



Fig. 11. — Transverse section through heart, ext. cut. External cuticle. 

 exi. w. ht. External wall of heart, int. Internal lining of heart, m. to. At. 

 Muscular wall of ieart. muse. Muscle-fibres from the heart to the fat- 

 bodies, forming a sort of pericardium, susp. muse. Suspensory muscle of the 

 heart. 



EiG. 12. — Section through the nerve-cord. ffne. Ganglionic part. /nc. 

 Fibrous part. 



Fig. 13. — Section through region of eye, showing two eye-spots and the 

 lens of another, r.e. Retinal cells, inner pgt. Pigment round the base of 

 the crystalline cones. /. Lens. h. e. Cells of the hypodermis. pfft. Pigment 

 around the base of the retinal cells. 



Fig. 14. — Section through the region of the eyes, showing one spot cut 

 horizontally and one longitudinally. A. An eye-spot cut longitudinally. B. 

 An eye-spot cut transversely. 1. Lens. pfft. Pigment, e. Crystalline cones. 



