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Fishery Bulletin 89(3), 1991 



1.0mm 



B 



Figure 2 



Eggs of Paralichthys calif ornicus: (A) stage VIII (LACM 053 SO 08 OB 01P), (B) dorsal view 

 of embryo, stage VIII (LACM 053 SO 08 OB 01P), (C,D) stage IX (LACM 047 OB 15 OB 02P), 

 (E,F) stage X (LACM 060 87 22 OB 01S). 



located near the oil globule, 

 encircles and then migrates 

 onto the side of the oil 

 globule nearest the embryo. 

 Pigment on the embryo 

 develops from the eyes to 

 the first somites along the 

 dorsal and dorsolateral sur- 

 faces, posteriorly along the 

 dorsum to the tip of the tail, 

 and on the ventral midline 

 of the free portion of the 

 tail (Figs. 1E,F). 



When stage IX begins, 

 pigment first migrates into 

 the dorsal finfold between 

 the nape and an area about 

 three-fourths the distance 

 from snout to tail tip and in- 

 to the ventral finfold oppo- 

 site the posteriormost dor- 

 sal finfold melanophores 

 (Figs. 2C,D). The migration 

 of pigment into the finfolds 

 continues during stage X 

 (Figs. 2E,F), forming a 

 continuous row of melano- 

 phores in the dorsal finfold 

 and a patch of pigment in 

 the ventral finfold. 



Xystreurys liolepis Xys- 

 treurys liolepis eggs are 

 pelagic with a smooth chor- 

 ion (0.72-0.90 mm), homog- 

 enous yolk (0.42-0.74 mm), 

 and a single oil globule 

 (0.14-0.24 mm, Table 1). 

 Early- through mid-stage 

 development of X. liolepis 

 eggs (stages II- VIII, Figs. 

 3A-F, 4A,B) is similar to 

 that of Paralichthys eali- 

 fornicus (Figs. 1A-F, 2A, 

 B) with few differences in 

 the developmental sequence 

 of the embryo, pigment, or 

 oil globule detected. At ap- 

 proximately stage IX, pig- 

 ment patterns of X liolepis 

 embryos begin to differ 

 diagnostically from those of 

 P. calif ornicus. 



Melanophore migration 

 into the medial finfolds oc- 



