from the natural environment. Regarding the 

 Pandalidae, Pike and Williamson (1964) have 

 shown variability in number of molts required to 

 reach the megalopa stage in the plankton for Pan- 

 dalina brevirostris (Rathke) and Pandalus pro- 

 pinquus G. O. Sars, and that larvae of Dichelopan- 

 dalus bonnieri (Caullery) and Pandalus montagui 

 Leach reared in the laboratory have more larval 

 stages than specimens from plankton. Berkeley 

 (1931) mentioned the possibility of variation in 

 number of molts in larvae of Pandalus danae 

 Stimpson. Kurata ( 1964) speculated that larvae of 

 P. borealis Kr0yer in Japanese waters may have 

 six or seven stages. 



I have observed that both P. borealis and P. 

 goniurus reared in the laboratory are capable of 

 prolonging their normal interval between zoeal 

 moltings (about 10-15 days) to as much as 5 wk, 

 and that P. borealis may have as many as 1 1 zoeal 

 stages before reaching the megalopa stage. Al- 

 though the causes of molt retardation and mor- 

 phological variation in pandalid larvae have not 

 been established, the potential for variability 

 exists not only in P. goniurus but in other pan- 

 dalids as well. Variability in larval development 

 from different geographical areas, therefore, is to 

 be expected. 



FISHERY BULLETIN; VOL. 76, NO. 1 



LITERATURE CITED 



Berkeley, A. A. 



1931. The post-embryonic development of the common 

 pandalids of British Columbia. Contrib. Can. Biol. 

 6(6):79-163. 

 COSTLOW, J. D., Jr. 



1965. Variability in larval stages of the blue crab, Cal- 

 linectes sapidus. Biol. Bull. (Woods Hole) 128:58-66. 



HAYNES, E. 



1976. Description of zoeae of coonstripe shrimp, Pandalus 

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

 74:323-342. 



IVANOV, B. G. 



1965. (A description of the first larvae of the far-eastern 

 shrimp {Pandalus goniurus).) [In Russ., Engl, summ.] 

 Zool. Zh. 44:1255-1257. (Translated by U.S. Dep. Com- 

 mer., NOAA, Natl. Mar. Fish. Serv., Div. Foreign Fish.) 



Kurata, H. 



1964. Larvae of decapod Crustacea of Hokkaido. 3. Pan- 

 dalidae. Bull. Hokkaido Reg. Fish. Res. Lab. 28:23-34. 

 (Transl., Fish. Res. Board Can., 1966, Transl. 693.) 



MAKAROV, R. R. 



1967. Larvae of the shrimps and crabs of the west Kam- 

 chatkan shelf and their distribution. Natl. Lending 

 Libr. Sci. Technol., Boston Spa, Yorkshire, 199 p. 



Pike, R. B., and D. L Williamson. 



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

 da). Crustaceana 6:265-284. 



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