HAYNES: LEBBEUS GROENLANDICUS LARVAE 



small setae occur along lateral margin. Antennal 

 scale distally divided into two segments and 

 fringed with 29 or 30 thin, plumose setae along 

 terminal and inner margins; distal outer projec- 

 tion a stout spine. Protopodite bears two stout 

 spines, one at base of flagellum and other at base of 

 scale. 



MANDIBLES, MAXILLULE, AND MAX- 

 ILLA. — Essentially identical to Stage I except 

 scaphognathite of maxilla usually bears 35 setae 

 along outer margin, in addition to the longer and 

 thicker seta at proximal end, and proximal cleft 

 slightly deeper. 



MAXILLIPEDS.— Essentially identical to Stage I 

 except exopodites of first, second, and third maxil- 

 lipeds bear 5, 16, and 16 natatory setae, respec- 

 tively. 



FIRST PEREOPOD (FIGURE 2D).— Segmented; 

 without exopodite; chela functional. 



SECOND PEREOPOD (FIGURE 2E).— Adult in 

 shape; chela functional; ischiopodite articulates 

 somewhat laterally with basipodite. No exopodite. 



THIRD TO FIFTH PEREOPODS.— Similar to 

 Stage I except ischiopodite articulates somewhat 

 laterally with meropodite and basipodite. 



PLEOPODS.— First pleopod slightly more de- 

 veloped than in Stage I but still only about one- 

 third length of second pleopod and without appen- 

 dix interna. Second pleopod ( Figure 2F) larger and 

 narrower than in Stage I; outer lamella about 

 one-fourth longer than inner lamella; both lamel- 

 lae and appendix interna fully segmented at their 

 bases. Third to fifth pleopods essentally identical 

 to second pleopods. 



ABDOMEN AND TELSON.— Posterolateral 

 spines on fourth and fifth abdominal somites still 

 present, those on fourth somite being only slightly 

 shorter in relation to length of somite than in 

 Stage I. Telson essentially identical to Stage I 

 except segmented from sixth abdominal segment 

 and bears 20 or 21 densely plumose setae. Uropods 

 still enclosed. 



STAGE III (MEGALOPA) 



Total length of Stage III 7.5 mm (range 7.4-7.6 

 mm; two specimens). Antennal spine of carapace 

 larger and pterygostomian spine smaller than in 

 Stage II; no evidence of minute spinules along 

 anteroventral margin. Rostrum (Figure 3 A) short; 

 bears single tooth at base in addition to dorsal 

 protuberance. Antennules similar in shape to 

 adult; outer flagellum six-segmented; inner flagel- 

 lum five-segmented; peduncle three-segmented, 



Figure 3. — Stage III (megalopa) of Lebbeus groenlan- 

 dicus: A, carapace; B, telson. 



0.5 mm 



463 



