138 CKESSWELL SHEARER, WALTER DE MORGAN, H, M. FUCHS. 



A large number of larval skeletons were examined at about ten days 

 old, drawings of which will appear in the forthcoming work, but in no 

 case was the inheritance at all affected. At a late stage (30-40 days), 

 again, a large number of Plutei were examined, but in no case could 

 any alteration in the inheritance of the posterior ciliated epaulettes, 

 the pedicellariae or the green pigment masses, be detected. Figs. 6 



";a.c4tf. 



Fig. 6.— Larva of ^. acutus i x E. viiUaris'i. Dorsal view. 28 days old. Fertilized 

 in water with raised OH-ion concentration, a. cil. cp. — Anterior ciliated 

 epaulette, gr. p. — Green pigment. I. 2^ed. — Lateral pedicellaria. tu. f. — 

 Tube-foot. 



and 7 show typical 28-day Plutei of the cross E. acutus ^ x E. 



Fig. 7. — Larva of £". acutus S x E. miUaris'i . A'entral view. 28 days old. Fertilized 

 in water witli lowered OH-ion concentration, a. cil. ep. — Anterior ciliated 

 epaulette, ech. r. — Echinus rudiment, gr. p. — Green pigment mass. I. ped. 

 Lateral pedicelhiria. 



