FISHERY BULLETIN; VOL. 73, NO. 4 



Mole 



Female 



6' '8 10' 'l2' 'l4' 'l6' 'l8 '20 

 Carapace Length (mm) 



Figure 7.— Length-frequency histx)granis of Bentheogennema 

 burkenroadi n. sp., from the five cruises (1972-73) off the Oregon 

 coast. 



shrimp captured were a 17-mm c.l. male and a 

 20-mm c.l. female. 



Since the mesh size of the net liner was small 

 enough to retain the young (6-7 mm c.l.) and we 

 assume equal chance of capture of young and 

 adults, then adults apparently live more than a 

 year or two after first spawning because the 

 number of adults captured is greater than the 

 number of immature. In fact, the 12- to 15-mm 

 mode must consist of greater than one age class 

 since by itself it exceeds the juveniles in number. 

 This overlap of age classes at >12 mm c.l. indicates 

 that growth slows after maturity is reached. 



ACKNOWLEDGMENTS 



We thank R. J. LeBrasseur (Fisheries Research 

 Board of Canada, Nanaimo, B.C. [POG]) and E. C. 

 Jones (Hawaii Area Fishery Research Center in 

 Honolulu [POFI]) for providing us with shrimp 

 specimens collected during their oceanographic 

 exploration. We thank Robert Carney for his aid 

 and instruction in the illustrations, and W. G. 

 Pearcy for his critical review and financial sup- 

 port. 



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