FISHERY BULLETIN; VOL. 76, NO. 1 



dorsal surface of the body above the abdomen. 

 Melanophores on the finfold at the tail vary 

 greatly; they are found both on the dorsal and 

 ventral body margins in varying numbers. A 

 single dendritic melanophore is present anterior 

 to the eye, and two or three more are posterior to 

 the eye. 



Six Through Eight Days Posthatching 



At this age, there is little difference in body form 

 and structure from that in Figure 2c. Standard 

 lengths at 160 h average 2.06 mm and range be- 

 tween 1.80 and 2.23 mm. The preopercle can be 

 seen on some larger specimens. 



Pigmentation has become more intense and is 

 expanding. Principal changes in the dendritic 

 pigments involve the ventral expansion of 

 melanophores on the upper surface of the abdo- 

 men, and the coalescence of tail pigmentation into 

 dark stripes. Indistinct pigment occurs from the 

 eye to the tip of the snout. Melanophores are still 

 found anterior to the anus and have increased in 

 number below the abdomen. A melanophore spot 

 is still found on the tip of the lower jaw. 



Nine Through Eleven Days 

 Posthatching (Figure 2D) 



During this 3-day period the larvae begin to 

 grow appreciably in length. By 11 days, standard 

 lengths average 2.92 mm and range from 2.37 to 

 3.48 mm. Six small teeth are present on the upper 

 jaw and four on the lower jaw at this age. The 

 preopercle is more evident and a small spine can 

 be seen. Branchiostegal rays are present for the 

 first time. The pectoral fin is still membraneous. 

 Some larvae have a presumptive hypural plate 

 below the notochord tip, but no notochord flexion is 

 observed. 



Pigmentation undergoes only minor changes in 

 this period. Principal body pigment gives the ap- 

 pearance of a dark stripe from snout to tail. 

 Melanophores are now evident on the lateral line 

 giving the impression of a series of dashes. Tiny 

 melanophores are present on the midlateral tail 

 region and both ahead of and behind the eye 

 within the pigment stripe. 



Twelve Through Fifteen Days 

 Posthatching (Figure 2E) 



Standard lengths at 12 days average 3.35 mm, 



and increase to 4.59 mm at 15 days. The preoper- 

 cular spine is prominent, and on the larger speci- 

 mens second and third spines are visible below the 

 first. By the 14th day (at a size of 4.4 mm SL) 

 notochord flexion has occurred in all specimens. 

 As many as 18 caudal rays are first seen at 13 days 

 (4.0 mm SL), and by 15 days (4.4 mm SL), 25 dorsal 

 rays and 10 anal rays are evident. Teeth are found 

 on both jaws (10 on the upper and 6 on the lower). 

 At this age, the pigmentation still gives the 

 appearance of a stripe from the snout through the 

 eye to the upper abdomen, and on the lateral line 

 and ventral tail surface. Melanophores are still 

 located at the tip and posterior to the angle of the 

 lower jaw, on the tip of the upper jaw, and along 

 the ventral margin of the abdomen. The spot an- 

 terior to the anus is indistinct. Pigmentation 

 around the eye is localized in an anterior and pos- 

 terior position within the pigment stripe. The den- 

 dritic melanophores on the upper abdominal sur- 

 face are still large and distinct. Dendritic 

 melanophores are heavily concentrated along the 

 lateral line and also along the ventral margin of 

 the tail. The dorsal tail margin has less pigmenta- 

 tion. A single large dendritic melanophore is 

 found on the base of the caudal fin. Other pigmen- 

 tation is widely scattered over the entire tail. 

 Seatrout preserved for long periods seem to lose 

 the melanophore on the caudal fin but other body 

 melanophores remain visible. 



GROWTH 



Larval spotted seatrout grew from about 1.5 mm 

 SL at hatching to about 4.5 mm SL in 15 days. A. 

 K. Taniguchi (pers. commun.) at the University of 

 Miami has observed faster growth of larval spot- 

 ted seatrout. He raised larvae at various tempera- 

 tures and fed them copepods. At 2 wk of age, we 

 noted cannibalism in our seatrout larvae even 

 though ample food of appropriate size appeared to 

 be present. 



Measurements were made of preserved larvae. 

 The data were tabulated according to size and age 

 (Table 1). Standard lengths of larvae were consis- 

 tently 93 to 95% of the total length until flexion of 

 the notochord occurred at 14 or 15 days; then the 

 standard length decreased to 88'yfof total length. 



Preanal lengths at 1 day posthatching were 44% 

 SL, 36% SL at 5 days, and 54% SL at 15 days. This 

 indicated that the preliminary decrease in gut 

 length appeared to be associated with yolk absorp- 

 tion. After 5 days, the gut length steadily in- 



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