JOURNAL, OF ENTOMOLOGY AND ZOOLOGY 221 



EXPLANATION OF FIGURES. DEVELOPMENT OF LIGYDA. 



Figures 1-33. Sketches of embryos or parts at various stages. Mostly taken from 

 freshly killed specimens. Figs. 1 to 8, 11-23, X50; Fig. 9, X 300 ; Fig. 

 10, XIOO. 



Figure 16. Side view of stage like 6 or 7. Fig. 17. Side of 8. 



Figure 18 of 11 or 12. Fig. 19 of 13. Fig. 20 of 14. Fig. 21 of 15. 



Figure 24. Sketch of an early stage of preserved egg. The cells are indicated as they 



show on the surface of the yolk. Near the center is a half ring of telo- 



blast cells. 

 Figure 26. Lower end of an early embryo, showing teloblast cell areas. The six cen- 

 tral cell rows are those which go to form the nervous svstem in part. 



X700. 

 Figure 25. ^^'hole mount of an early embryo. The appendages begin to show. X70. 

 Figure 27. Later stage surface mount. X 70. 

 Figure 28. Surface preparation of one-half the optic lobe and brain region of an 



embryo such as shown in Fig. 6. The dorsal side is at the top. X460. 

 Figure 29. Surface view of one-half of brain and optic lobe region of an embrvo 



like Fig. 8. X460. 

 Figure 30. Surface view of body ganglion of embryo like Fig. 8. X460. 

 Figure 31. Optic lobes and brain one side, embryo such as Figs. 12 or 13. X700. 

 Figure 32. Thoracic ganglion from above, from embryo 12 or 13. X460. 

 Figures 33 to 49. Sections of ganglia of various stages. All X70. Ventral side up 



in 33 to 39, 48 and 49. Cephalic side up in 40, 41, 44, 45, 46, 47. 

 Figures 33 and 34. Cross section of body ganglia of 11. 

 Figure 35. Median longitudinal section of ganglia of 11. 

 Figures 36 to 39. Cross sections of body ganglia of a 2.5 mm. embryo. 

 Figures 40 and 41. Sections of one-half brain of a 2.5 mm. embryo. 

 Figure 42. Longitudinal section cephalic ganglia of a 2.5 mm. embryo. 

 Figure 43. Longitudinal section abdominal ganglia of a 2.5 mm. embryo. 

 Figures 44 and 46. Longitudinal sections at different levels of the abdominal ganglion 



of a 3.5 mm. embryo. 

 Figure 45. Frontal longitudinal section of one-half the brain of a 3.5 mm. embryo. 

 Figure 47. Section of one-half a brain of an embryo about the stage of Fig. 15. 

 Figure 48. Longitudinal section of abdominal ganglia of the last. 

 Figure 49. Cross section, body glanglion of the last. 



