330 



DISCOVERY REPORTS 



optical combination. Such an elaboration of structure must have a marked effect on its 

 functional properties. The cuticle of the limb is continuous over the outer face of the 

 lens (Fig. lo, ait.). 



An annular depression surrounds the lens near its periphery and is seen clearly in 

 Fig. 10. It is produced by folding of the integument which is very thin and delicate 

 in this region and resembles an arthrodial membrane. A similar folding of the integu- 

 ment was observed by Kemp {igiob, p. 644) in S. debilis, and led him to suggest that 

 the photophores might thereby be permitted some degree of movement, although no 

 related musculature was found. In Hoplophonis a well-developed musculature is 

 present, and will be described later. 



Fig. 10. Section cut diametrically through one of the boss-shaped photophores borne on the bases of the pleopods of 

 Hoplophorus novae-zealandiae. A similar section is seen in Plate XXV, fig. i. Fixed Duboscq, Delafield's haematoxylin 

 and eosin. cut. cuticle; cyt.phot.c. cytoplasm of photogenic cell; f.r. fibrous reflector; o;-. 3. granular zone at bases of 

 photogenic cells; /./. inner layer of lens; l.m. middle layer of lens; l.m'. subsidiary intermediate layer of lens; l.o. outer 

 layer of lens; n.phot.c. nucleus of photogenic cell; n.r.c. nucleus of reflector tissue ;7.5'. junction zone between the fibres 

 of the photophore nerve and the striated zone; phot.c.cl.a. clear area of photogenic cell; phot.l.m.a. attachment of 

 longitudinal photophore muscle; phot.m.l. photophore muscle loop (seen clearly in Fig. 12) cut transversely; phot.nv. 

 photophore nerve; stri.s. striated zone. 



