Fig. 14. Transverse section through an embryo of the same age as fig. 5, passing through an abdominal segment above and a thoracic segment below.
Fig. 15. Longitudinal section slightly to one side of the middle line through an embryo of the same age.
Fig. 16. Transverse section through the ventral plate in the thoracic region of an embryo of the same age as fig. 7.
Fig. 17. Transverse section through the procephalic lobes of an embryo of the same age. gr. Section of hemicircular groove in procephalic lobe.
Fig. 18. Transverse section through the thoracic region of an embryo of the same age as fig. 8.
Fig. 19. Section through the procephalic lobes of an embryo of the same age.
Fig. 20a, b, c, d, e. Five sections through an embryo of the same age as fig. 9. a and b are sections through the procephalic lobes, c through the front part of the thorax. d cuts transversely the posterior parts of the thorax, and longitudinally and horizontally the ventral surface of the abdomen. e cuts the posterior part of the abdomen longitudinally and horizontally, and shews the commencement of the mesenteron.
Fig. 21. Longitudinal and vertical section of an embryo of the same age. The section passes somewhat to one side of the middle line, and shews the structure of the nervous system.
Fig. 22. Transverse section through the dorsal part of the abdomen of an embryo of the same stage as fig. 9.