mature yolk-filled oocytes O400 /xm) were col- 

 lected in February. Since only a small fraction of 

 my February sample was gravid, the spawning 

 period for the majority of the population under 

 study appeared to encompass March-May (Table 

 1). The smallest reproductively active female mea- 

 sured 114 mm standard length ( SL); the largest 172 

 mm SL. Gonosomatic indices were at maximum 

 sizes in March (Figure 1) and a progressive de- 

 crease was indicated through spring with minimal 

 sizes occurring by June. A May increase in the 

 incidences of follicular atresia indicated the end of 

 spawning was near. Atretic oocytes are most 

 abundant near the termination of spawning when 

 oocytes that initiated but failed to complete yolk 

 deposition degenerate. 



My observation of follicles in various stages of 

 yolk deposition during ,the spawning period 

 suggests that successive batches of eggs are ma- 

 tured and spawned. The number of spawnings per 

 individual per season are not known, but the pres- 

 ence of a mode of mature oocytes (imminent 

 spawning), postovulatory follicles (transitory 

 remnant of the follicle wall from a recent spawn- 

 ing), and a vitellogenic oocyte mode for a sub- 

 sequent spawning indicates that females are ca- 

 pable of spavming more than once per season. 

 Postovulatory follicles were similar in morphol- 

 ogy to those reported in other teleosts (Hunter and 

 Goldberg 1980). 



Discussion 



Peprilus simillimus undergoes a distinctly 

 seasonal spawning cycle characterized by an 

 abrupt increase in ovarian sizes during late 

 winter with spawning essentially completed by 

 the end of spring. Fitch and Lavenberg (1971) re- 

 ported that spawning may extend into July. Horn 

 (1970) similarly reported that spawning in P. 

 triacanthus, P. burti, P. paru, and P. simillimus 

 generally occurs in spring and early summer. This 

 contracted type of cycle differs from that of some 

 southern California fishes that have a consider- 

 ably longer spawning period. Goldberg (1980) re- 

 ported that gravid female Chitonotus pugetensis 

 and Icelinus quadriceriatus (both Cottidae) were 

 found throughout the year with maximum num- 

 bers in winter and early spring. The northern an- 

 chovy, Engraulis mordax, may have the ability to 

 spawn all year but is likely limited by food avail- 

 ability and energy reserves (Brewer 1978; Hunter 

 and Goldberg 1980). 



The P. simillimus spawning cycle is more rem- 

 iniscent of northern fishes (Quasim 1956), which 

 have a short reproductive period (generally 

 winter-early spring) with a single spawning. The 

 multiple spawnings over a brief period exhibited 

 by P. simillimus may represent a compromise be- 

 tween a short reproductive period with a single 

 spawning (characteristic of high latitude fishest 

 and a long reproductive period with repeated 

 spawnings typical of tropical fishes (Nikolsky 

 1963). 



Acknowledgments 



I am grateful to Edward DeMartini and Robert 

 Fountain (University of California at Santa Bar- 

 bara) for assistance in obtaining specimens. Trang 

 Nguyen assisted with histological preparations. 

 This study was aided by a Whittier College faculty 

 research grant. 



Literature Cited 



Brewer. G. D. 



1978, Reproduction and spawning of the northern anchovy, 

 Engraulis mordax. in San Pedro Bay, California. Calif. 

 Fish Game 64:175-184. 



FITCH. J. E., AND R. J. Lavenberg. 



1971. Marine food and game fishes of California. Univ. 

 Calif. Press. Berkeley, 179 p. 



GOLDBERG, S. R. 



1980. Seasonal spawning cycles oftwo marine cottid fishes, 

 Chitonotus pugetensis and Icelinus quadriceriatus from 

 southern California. Bull. Mar Sci. 30:131-135. 

 HORN, M. H. 



1970. Systematics and biology of the stromateid fishes of 

 the genus Pepn/ws. Bull. Mus. Comp.Zool. 140:165-261. 

 HUNTER, J. R., AND S. R. GOLDBERG. 



1980. Spawning incidence and batch fecundity in northern 

 anchovy, Engraulis mordax. Fish. Bull., U.S. 77:641- 

 652. 

 MILLER, D. J., AND R. N. LEA. 



1972. Guide to the coastal marine fishes of California. 

 Calif. Dep. Fish Game, Fish Bull. 157, 235 p. 



NIKOLSKY, G. Y 



1963. The ecology of fishes. Acad. Press, N.Y., 352 p. 

 OLIPHANT. M. S. 



1979. Califoniia marine fish landings for 1976. Calif. 

 Dep. Fish Game, Fish Bull. 170, 56 p. 



Quasim, S. z. 



1956. Time and duration of the spawning season in some 

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21:144-154. 



STEPHEN R. GOLDBERG 



Department of Biology 

 Whittier College 

 Whittier. CA 90608 



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