FISHERY BULLETIN: VOL, 69. NO. 1 



Exopod: 



Four long ventrolateral; 

 two long, one medium, 

 and one short terminal. 



Same as Nauplius I. 



Figure 4. — Nauplius III, ventral view. 



long terminal; one short 

 dorsolateral. 

 Second antenna: 



Endopod: Two short ventrolateral; 



three long terminal. 

 Exopod: Three long ventrolateral; 



three long and one short 

 terminal. 

 Mandible: Same as Nauplius I. 



NAUPLIUS IV 



(Fig. 5) 

 Mean TL = 0.44 mm (0.41-0.47 mm) 

 Mean W =0.21 mm (0.20-0.22 mm) 



N = 35 



The posterior portion of the body has become 

 more slender and two definite rounded furcal 

 processes are formed, each one with six spines. 

 The small dorsomedian spine on the body is 

 absent and does not reappear in later substages. 

 Ventral appendages (first and second maxillae 

 and first and second maxillipeds), still covered 

 by the cuticle, are visible posterior to the man- 

 dibles. Frontal organs are present. 



Setation of appendages: 



First antenna: Same as Nauplius III. 

 Second antenna: 



Endopod: Two short ventrolateral; 



one short and three long 

 terminal. 



Figure 5. — Nauplius IV, ventral view. 



NAUPLIUS V 



(Fig. 6) 



Mean TL = 0.50 mm (0.43-0.58 mm) 



Mean W = 0.20 mm (0.18-0.22 mm) 



N = 41 



The body is further elongated and the furcal 

 processes are more pronounced, each giving rise 

 to seven spines. The maxillae and maxillipeds 

 are now external and show more advanced de- 

 velopment. The swelling at the base of the 

 mandible is large and prominent and has a 

 masticatory surface composed of several rows 

 of small teeth. The endopod and the exopod of 

 the mandible are frequently hollow and trans- 

 parent. The outline of a developing carapace 

 can be seen on the dorsal surface of the body, 

 and frontal organs are present. 



In living specimens, eyes and an anal canal 

 are visible internally. In preserved specimens, 

 the anal canal appears to open externally. 



It was not possible to determine if the ap- 

 pendages were truly segmented. The append- 

 ages of some specimens appeared segmented, 

 i.e., their surfaces possessed annular indenta- 

 tions; those of others did not. 



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