FISHERY BULLETIN: VOL. 73, NO. 2 



Table Z.—Diplophos taenia, computation of rank-sum index of 

 meristic counts and comparison with rank-sum index of produc- 

 tivity (from Table 1). Values are given as mean (number of 

 specimens). 



Table A.—Diplophos taenia. Comparison of rank-sum index of 

 meristic counts (from Table 3) with temperature at 100 m ranked 

 over the six Pacific areas. Temperature data taken from Brinton 

 (1962). 



Rank 



Area 



Counts 



Temperature 



CNP 



PS 



WEP 



CEP 



SCS 



ETP 



5 



3.5 



1 



2 



3.5 



6 



Tau. = +0.13, P>0.20 



given by Brinton (1962). The 100-m depth was 

 chosen arbitrarily, but the conclusion holds if sur- 

 face temperatures, whether summer or winter, are 

 chosen. Meristic counts for D. taenia are lowest in 

 specimens from the eastern tropical Pacific where 

 temperature values are also the lowest. This is 

 exactly opposite to the result expected if 

 temperature were involved in determining the 

 meristic variation observed over the six areas. In 

 fact the data show no relationship between 

 meristic counts and temperature for these areas. 

 Values of salinity in the open ocean are far too 

 conservative to be involved in determining the 

 observed variation (Hubbs 1925; Sverdrup et al. 

 1942; Barlow 1961; Blackburn 1967). Although the 

 eastern tropical Pacific is well known for a marked 

 oxygen minimum layer (Brandhorst 1959), and 

 oxygen concentration variation may affect the 

 development of meristic characters (Alderdice et 

 al. 1958; Garside 1959, 1966), in all eight areas 

 oxygen is essentially saturated in the wind-mixed 



surface layer where the larvae and probably the 

 eggs of D. taenia occur. The low counts (relative to 

 other areas) of specimens of D. taenia from the 

 eastern tropical Pacific run counter to what might 

 be expected if dissolved oxygen concentrations 

 were involved in determining the observed meris- 

 tic variation. 



The rank-sum indices of meristic counts and 

 productivity are significantly and negatively 

 correlated (tau g = -0.893, P < 0.01, Table 3). 



Pollichthys mauli (Poll) 



Pollichthys mauli ranges from the western 

 North Atlantic to the Philippine Sea. We have 

 examined specimens of this species from the Gulf 

 of Guinea, and the Philippine and South China 

 seas. Results for IPVALA photophore counts (Ta- 

 ble 5) parallel the results for Diplophos taenia; the 

 counts from Philippine Sea specimens are sig- 

 nificantly higher than counts from specimens from 

 the South China Sea and Gulf of Guinea. 



Table b.-Pollichthys mauli, IPVALA photophores. 



Vinciguerria lucetia Garman 



Vinciguerria lucetia is endemic to the eastern 

 Pacific (Ahlstrom and Counts 1958; Craddock and 

 Mead 1970; Gorbunova 1972). The work of Ahl- 

 strom and Counts (1958) has made the early life 

 history of V. lucetia the best known of any of the 

 species included in this report. We have not 

 examined any specimens of V. lucetia in connec- 

 tion with this work, but the following results of the 

 study of this species by Ahlstrom and Counts 

 (1958) seem to be particularly relevant to this 

 paper: 1) In V. lucetia the total number of myo- 

 tomes is formed in late-stage eggs, prior to 

 hatching. 2) Metamorphosis in V. lucetia is 

 marked by a period of rapid change in body 

 proportions without a marked change in standard 

 length. The completion of metamorphosis is sig- 

 naled by the complete development of all pho- 

 tophores, including the late-forming photophores 

 of the posterior VAV and mid- AC segments. 3) 

 Metamorphosis occurs at a smaller size south of 

 lat. 25°N than north of lat. 27.5°N, with meta- 



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