FISHERY BULLETIN: VOL. 84, NO. 1 



mitotic 



notochord 



swim brain 

 muscle bladder 



Figure b— Trachurus symmetricus larva, 3.75 mm SL. All 11 histological criteria graded as healthy. Bar = 281 ^m. 



Figure 6— Head of Trachurus symmetricus larva graded healthy. Mitotic activity and the location of brain lesions are indicated. Bar 

 = 47 \im. B = brain. 



Figure 1— Trachurus symmetricus larva graded as starving. Lesions present throughout brain and spinal cord. Bar = 47 ^m. B = 

 brain, N = notochord. 



Figure 8— Pectoral area of a dying Trachurus symmetricus larva showing darkly stained primitive nerve cells, wavy muscle fibers, necrotic 

 and atrophied liver, and loss of integrity of midgut mucosal cells. Bar = 47 ^m. FG = foregut, L = liver, m = muscle, MG = midgut, 

 N = notochord, SB = swim bladder, SP = spinal cord. 



Figure 9— Pectoral area of healthy Trachurus symmetricus larva collected offshore showing parallel muscle fibers and abundant inter- 

 muscular tissue, distinct nuclei in liver and midgut, and good cellular integrity. Note deflating swim bladder. Bar = 47 ^m. FG = foregut, 

 IM = intermuscular tissue, L = liver, M = muscle, MG = midgut, N = notochord, P = pancreas, SB = swim bladder. 



Figure 10— Pectoral area of healthy Trachurus symmetricus larva collected near San Clemente Island showing abundant glycogen reserves 

 in the liver. Bar = 47 y.m. FG = foregut, L = liver, M = muscle, MG = midgut, N = notochord, P = pancreas, SB = swim bladder. 



8 



