LAROCHE and RICHARDSON: REPRODUCTION OF NORTHERN ANCHOVY 



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Figure 3. — Photomicrographs of degenerating ovarian oocytes from Engraulis mordax. a. Degenerating oocytes (arrows) from a 

 northern anchovy captured in July ( x25). b. Degenerating oocytes with abnormal nuclei (arrows) from a ripe northern anchovy 

 captured in July ( x25). c. Degenerating oocytes (arrows) from a northern anchovy captured in May ( x25). d. Degenerating ripe oocytes 

 (arrows) from a northern anchovy captured in July (xl2.5). 



more mature, degenerating oocytes the yolk ap- 

 peared mottled and often the outline of the oocyte 

 was irregular (Figure 3c). Ripe, ovulated oocytes 

 that were degenerating differed from normal ones 

 primarily in the appearance of the yolk. Instead of 

 the honeycomblike, segmented yolk of normal 

 oocytes, yolk in degenerating, ripe oocytes was 

 either a solid opaque mass, or was dispersed into 



individual globules that looked like oil droplets 

 (Figure 3d). 



Oocyte Size-Frequency Distributions 



Oocyte growth was traced through the compos- 

 ite size-frequency curves of 51 northern anchovies, 

 representing nine stages of ovarian development, 



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