ORGANS OF SPECIAL SENSE 



167 



cell (fig. 8, NAC). The lateral part of its cytoplasm, however, 

 has assumed a definite cup-like contour, and in its fixed condi- 

 tion, shows concentric lamellae with which the pigment of the cell 

 is associated (fig. 8, Pg). The mouth of this cup is directed 



F^:^:::::^:^^^^^ 



Text tig. B Reconstructed drawing of the central nervous system and organs 

 of special sense; dorsal aspect. C, dorsal commissure. DG, dorsal ganglion; 

 E, eye; P, pharynx; NPh, pharyngeal sheath nerves; NCP, nerve of ciliated pit. 



laterally and is closely applied to the convex surface of the 

 retinular cell (fig. 8, NVC). 



The retinular cell appears to be a modified nerve element. 

 Its nucleus has the characteristic spheroidal contour of that of 

 a typical nerve cell. In the fixed condition, the cytoplasm of 



