16 MARIE A. HINKICHS. 



EXPLANATION OF PLATE II. 



FIGS. 31-32. Normal two-day larvae. 



FIGS. 33-39. Effect of development in more concentrated solutions of sensi- 

 tizing dyes in the dark. Figs. 33-36 show differential inhibition. Figs. 37-39 

 show differential acclimation. (Figs. 33, 34, 37, 38, development in eosin solution 

 in the dark. Figs. 35, 39, benzoflavine, dark. Fig. 36, methylene blue, dark.) 



FIGS. 40-41. Overproduction in the number of aboral arms. Fig. 40. Un- 

 stained sperm exposed to radiation from photographic bulb for 30 minutes X normal 

 egg. Fig. 41. Stained sperm (stained in the dark for 30 minutes before fertilizing 

 normal eggs.) 



FIGS. 42-47. Effect of light action alone. (No previous sensitization.) Figs. 

 42-45 show differential inhibition. Figs. 46, 47 show differential recovery. (Figs. 

 42, 43, 44. Two-day larva? exposed to direct sunlight for 90 minutes, immediately 

 after fertilization. No previous staining. Fig. 45. Two-day larvae. Exposed to 

 radiation from photographic bulb for 7 minutes. No previous staining. Figs. 

 46, 47. Six-day larvae. Exposed to direct sunlight for 90 minutes. No previous 

 staining.) 



FIGS. 48-63. Effect of fertilizing normal eggs with photodynamically treated 

 sperm. Fig. 48. Normal two-day larva. Control. Fig. 49. Differential inhi- 

 bition followed by slight differential acclimation. Normal eggs fertilized by cosin- 

 stained sperm exposed to radiation from photographic bulb for one minute. Figs. 

 50, 51. Exogastrulae produced as a result of fertilizing normal eggs with sperm, 

 eosin-stained, and exposed as above for 4 minutes. Figs. 52, 53, 55, 56 show 

 differential inhibition. (Fig. 55 is result of exposing eosin-stained sperm to dii 

 daylight for 30 minutes. Figs. 52, 53, 56, are the result of a zo-minute exposure of 

 sperm before fertilization.) Fig. 54. General recovery. Appears normal. Normal 

 eggs fertilized with eosin-stained sperm which had been exposed to radiation from 

 photographic bulb for i minute. Fig. 57. General recovery. Stained sperm li.nl 

 been exposed for 30 minutes to radiation from bulb. Figs. 58-63. Different i.. I 

 acclimation. Fig. 58. Stained sperm exposed for one minute. Radiation tiom 

 bulb. Figs. 59, 60. Result of 4-minute exposure. Figs. 61-63. Ten-minute 

 exposure. 



