immature fish was 285 mm. From the western 

 Atlantic, the smallest mature fish (stage 3) was 

 309 mm and the largest immature fish was 

 307 mm. There is an indication from the speci- 

 mens we examined that the eastern Atlantic 

 Afizis mature at a slightly smaller size than the 

 western Atlantic Auzis. It is possible, however, 

 that this is an artifact resulting from our sample 

 size. Table 1 also indicates the length distri- 

 bution of specimens used in our study. The two 

 specimens captured off Cape Hatteras were 458 

 and 459 mm and both had stage 3 ovaries. These 

 are not included in Table 1. 



Ovaries in stages 3 and 4 were taken as evi- 

 dence that spawning was imminent. Auxis with 

 ovaries in a spawning condition were captured 

 from the eastern Atlantic in February, March, 

 April, June, September, and October, and from 

 the western Atlantic in March and April. The 

 two specimens from off Cape Hatteras were cap- 

 tured in July and August, and both contained 

 ovaries in spawning condition. The number of 

 Auxis examined in each stage of ovary develop- 

 ment by month and area of capture is shown in 

 Table 2. 



The results show that Auxis from 360 to 

 455 mm fork length release from 56,000 to 

 148,000 eggs (Table 3). Rao (1964) determined 



Table 3. — Estimated number of eggs in the most ad- 

 vanced mode for Aiixis of different lengrths. 



Fork length 

 (mm) 



Eggs in the most 

 advanced mode 



360 



3<51 

 396 

 440 

 455 



95,000 

 58,000 

 56,000 



148,000 

 103,000 



that a 442-mm frigate mackerel captured off the 

 southwest coast of India would have released 

 280,000 eggs at next spawning. A large vari- 

 ation should be expected due to the small sample 

 size. The equation describing our regression 

 line calculated by the method of least squares is 



Y = —127.262 + 0.542X, 



where Y is the number of eggs in the most ad- 

 vanced mode in thousands and X is the fork 

 length of the fish in millimeters. 



Acknowledgments 



Table 2. — Number of Auxis examined in each stage of 

 ovary development by month and area of capture. 



Area Stage Feb. Mar. Apr. June July Aug. Sepl Oct. 



Eastern Atlantic 1 8 



2 „ 4 2 „ .. .. .. 10 



3 1 12 7 2 „ -_ 10 2 



4 __ .. .. .. .. .. ._ 6 



Western Atlantic 1 4 



2 — .- 1 ._ -_ .. ._ __ 



3 — 2 3 — — 



Cape Hatteras, 

 N.C. 3 -__-.... 1 1 .. .. 



The number of eggs released per spawning 

 is estimated for five specimens that contained 

 stage 4 ovaries. These were captured off the 

 Ivory Coast on 15 October 1967 at lat 4°31'N, 

 long 5°18'W. The method used to determine the 

 number of eggs released per spawning was to 

 estimate the number in the most mature modal 

 group, assuming that these eggs would be re- 

 leased at next spawning (Simmons, 1969). 



We thank Grant L. Beardsley, Jr., for his 

 valuable advice during the course of the inves- 

 tigation and Edward D. Houde for his useful 

 criticism of this manuscript. 



Literature Cited 



Clark, F. N. 



1925. The life history of Leuresthes tenuis, an 

 atherine fish with tide controlled spawning habits. 

 Calif. Fish Game Comm., Fish Bull. 10, 51 p. 

 Dragovich, a. 



1970a. The food of skipjack and yellowfin tunas in 

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 1970b. The food of bluefin tuna (Thunnus thyn- 

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 Am. Fish. Soc. 99:726-731. 

 Rao, K. V. N. 



1964. An account of the ripe ovaries of some In- 

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