356 MESSRS. C. SHEARER, W. DE MORGAN, AND H. M. FUCHS 



Fig. 40. — Six-armed pluteus. 24 days. X 55. From the dorsal aspect. Com- 

 mencement of preoral arms and anterior ciliated epaulettes. 



Fig. 41. — Eight-armed pluteus. 26 days. X 55. From the dorsal aspect. Ecliinus- 

 rudiment on the right side, which is exceptional. Anterior and posterior 

 ciliated epaulettes present. 



Fig. 42. — Pluteus. 30 days. X 55. From the dorsal aspect. Anterior and 

 posterior ciliated epaulettes and posterior pedicellaria present. 



Fig. 43. — Pluteus. 48 days. X 55. From the postero-ventral aspect. Large 

 ^c/(Mms-rudiment. Commencement of retraction of arms. The posterior 

 ciliated epaulettes form almost a complete ring round the body. 



Figs. 44-52. — E. esculentus^ X E. miliaiis $ , 1909-11. 



Showing, in the fully-formed plutei, the maternal inheritance of the posterior 

 ciliated epaulettes and absence of green pigment masses. 



Fig. 44.— Gastrula. 65 hours. X 175. 



Fig. 45. — Prism larva. 4 days. X 100. From the right side. Postoral arms 

 developing. 



Fig. 46. — Early pluteus. 7 days. X 100. From the dorsal aspect. Commence- 

 ment of the antero-lateral arms. 



Fig. 47. — Pluteus. 7 days. X 100. From the dorsal aspect. Further developed 

 than the preceding. Posterior pole rounded. 



Fig. 48. — Pluteus. 9 days. X 100. From the dorsal aspect. Commencement of 

 the postero-dorsal arms. 



Fig. 49. — Pluteus. 12 days. X 55. From the ventral aspect. Appearance of the 

 preoral arms and of the anterior ciliated epaulettes. 



Fig. 50. — Pluteus. 15 days. X 55. From the dorsal aspect. Appearance of 

 ^c/wmis-rudiment. 



Fig. 51. — Pluteus. 25 days. X 55. From the dorsal aspect. Commencement of 

 posterior ciliated epaulettes. 



Fig. 52. — Fully-formed pluteus. 36 days. X 55. From the dorsal aspect. The 

 £'c/(Mms-rudiment is seen with projecting tube-feet. Anterior and 

 posterior ciliated epaulettes and posterior pedicellaria are present. 



Plate 21. 



Figs. 53-59. — E. miliaris^ X E. esculentus $ , 1909-11. 



Showing, in the fully-formed plutei, the maternal inheritance of the green pigment 

 masses and absence of posterior ciliated epaulettes. 



Fig. 53. — Prism larva. 65 hours. X 175. From the ventral aspect. Commence- 

 ment of antero-lateral and postoral arms. 



