tion, Stage I zoeae of C. septemspinosa can be dis- 

 tinguished from Stage I zoeae of C. franciscorum 

 angustimana by the exopodites of the maxilhpeds. 

 The exopodites of the maxillipeds are jointed in 

 Stage I zoeae of C. septemspinosa and are not 

 jointed in Stage I zoeae of C. franciscorum angus- 

 timana. Also, the fifth pair of telson spines are 

 distinctly shorter than the fourth or sixth pair in 

 C. septemspinosa: whereas, in my Stage I zoeae of 

 C. franciscorum angustimana, the fifth pair of tel- 

 son spines are about equal in length to the fourth 

 and sixth pairs. 



The occurrence in later zoeal stages of func- 

 tional exopodites on the first pair of pereopods but 

 not on pereopodal pairs 2-5 has been used as a 

 criterion for distinguishing larvae of the genus 

 Crangon from larvae of other genera of the family 

 Crangonidae( Williamson 1960). 



I found buds of exopodites on both the first and 

 second pair of pereopods in Stage I zoeae of C. 

 franciscorum angustimana. Assuming zoeae of C. 

 franciscorum angustimana undergo typical de- 

 velopment for crangonid larvae, these buds will 

 become functional exopodites at Stage III or IV 

 (Needier 1941; Kurata 1964; Makarov 1967). The 

 criterion of the absence of exopodites on the second 

 pair of pereopods for distinguishing larvae of 

 Crangon from other genera of the Crangonidae, 

 therefore, is invalid for the North Pacific Ocean. 

 Unfortunately, larvae are described for only a few 

 species of crangonids from the North Pacific 

 Ocean, including the genus Crangon, and 

 confirmation of the generic characteristics of the 

 larvae is needed. 



Acknowledgment 



I thank Terry Butler, Pacific Biological Station, 

 Nanaimo, British Columbia, Canada, for identify- 

 ing the ovigerous females. 



Literature Cited 



haynes. e. 



1976. Description of zoeae of coonstripe shrimp, Pandalus 

 hypsinotus, reared in the lalMratory. Fish. Bull., U.S. 

 74:323-342. 

 IVANOV.B. G. 



1971. The larvae of some eastern shrimps in relation to 

 their taxonomic status, [in Russ.Engl. summ ] Zool Zh. 

 50:657-665 

 Kurata. H. 



1964 Larvae of decapod Crustacea of Hokkaido. 4. Cran- 

 gonidae and Glyphocrangonidae. [in Jpn.. Engl, summ.] 

 Bull. Hokkaido Reg. Fish. Res. Lab. 28:35-50. (Translated 



by Division of Foreign Fisheries, Natl. Mar. Fish. Serv., 



NOAA.) 

 LOVELAND.H. A..JR, 



1968. Larval development under laboratory conditions of 



Crangon alaskensis Rathbun. (Crustacea:Decapo- 



da). M.A. Thesis. Walla Walla Coll., Walla Walla, Wash., 



22 p. 

 Makarov. R. R. 



1967. Larvae of the shrimps and crabs of the west 



Kamtschatkan shelf and their distribution. (Translated 



from Russ. by B. Haigh. ) Natl. Lending Libr. Sci. Technol , 



Boston Spa. Yorkshire, 199 p. 

 NEEDLER.A. B. 



1938. The larval development of Pandalus stenolepis. J. 



Fish. Res. Board Can. 4:88-95. 

 1941. Larval stages of Crago septemspinosus Say. Trans. 



R. Can. Inst. 23:193-199. 



PIKE, R. B., .\ND D. I. Williamson 



1961. The larvae of Spirontocaris and related genera (De- 

 capoda, Hippolytidae). Crustaceana 2:187-208. 



1964. The larvae of some species of Pandalidae (Decapo- 

 da). Crustaceana 6:265-284. 

 Tesmer, C. a. , and a. C. Broad 



1964. The larval development of Crangon septemspinosa 

 (Say) (Crustacea:Decapoda). Ohio J. Sci. 64:239-250. 



Williamson, D.I. 



I960. Crustacea, Decapoda: Larvae VII. Caridea, Family 

 Crangonidae, Stenopodidea. Cons, Int. Explor. Mer, 

 Fiches Identification Zooplankton 90. 5 p 



EvanHaynes 



Northwest and Alaska Fisheries Center Auke Bay Laboratory 



National Marine Fisheries Service, NOAA 



P.O Box 155 



Auke Bay. AK 99821 



LENGTH-WEIGHT RELATIONSHIPS OF 



WESTERN ATLANTIC BLUEFIN TUNA, 



THVNNUS THYNNUS' 



The Atlantic bluefin tuna, Thunnus thynnus, is 

 seasonally distributed over most of the North At- 

 lantic Ocean from Newfoundland to Brazil and 

 from Norway to the Canary Islands (Gibbs and 

 Collette 1967). There has been a great reduction in 

 the Atlantic-wide catch ( including Mediterranean ) 

 from 38,500 metric tons (t) in 1964 to 12,500 t in 

 1973 (Miyake et al. 1974). Because of this, a 

 number of studies have been made and are being 

 continued in order to understand the reason for 

 this decline (Parks 1977; Shingu and Hisada 

 1977). 



'Contribution Number SEFC 80-OlM, Southeast Fisheries 

 Center Miami Laboratory, National Marine Fisheries Service, 

 NOAA, Miami. Fla. 



FISHERY BULLETIN: VOL, 77. NO. 4, 1980, 



995 



