KNICHT and OMORI: LARVAL DKVKLOl'MKNT OF SERGh'STKS SIMIUS 



Figure 6.— Sergestes similis. Maxillule: a, protozoea I; b, protozoea II, coxal and basal endites; c, protozoea III, basal endite; 



d, zoea I; e, postlarva I. 



with segments delineated; abdomen and telson 

 as in preceding stage. 



Antennule (Fig. 2f) with 4 subdivisions of 

 proximal segment and distal segment with 9 

 processes, including 5 setae and 4 aesthetascs. 



Mandibles (Fig. 4e) with median armature 

 asymmetrical, right mandible with 2 and left 

 mandible with 5 strong spines, the spine nearest 

 molar area is strongest on each mandible, 2 long 

 spines on right mandible separated by short 

 tooth. 



Maxillule (Fig. 6b) with 6 setae on basal endite 

 and 6 or 7, usually 7, setae on coxal endite. 



Maxilla (Fig. 7b) with setation of 8-4-5-5 on 

 medial lobes. 



First maxilliped with 7 or 8, usually 8, setae on 

 coxa. 



Second maxilliped with endopod setation of 2- 

 2-2-5; basis with 5 or 6, rarely 6, setae. 



Third maxilliped a small rudiment, some- 

 times slightly bifid at tip. 



Anlagen of thoracic legs 1-5 may be visible. 



Trotozoea III (Fig. 11a, b) 



Body length: 1.90 mm (0.18). 



Carapace with 1 pair supraorbital processes 

 which curve dorsolateral^ in addition to arma- 

 ture of preceding stage; all processes but 

 rostrum armed with strong spines which branch 



225 



