FISHERY BULLETIN: VOL. 71, NO. 3 



lections were made (Figure 1) changed for 

 each of the three series of cruises (Joseph, 

 Massmann, and Norcross, 1960; Massmann, 

 Norcross, and Joseph, 1961; Massmann, Joseph, 

 and Norcross, 1962). All collections were 

 made in the Chesapeake Bight between lat. 

 36° and 38 °N and from near shore to 80 nau- 

 tical miles offshore. Gear, depths of sampling, 

 and tow times were modified throughout the 

 cruises (Joseph et al., 1960; Norcross, Mass- 

 mann, and Joseph, 1961; Wilson, 1962). Meter 

 and half-meter nets and the Gulf III high 

 speed plankton sampler (Gehringer, 1952, 

 1962; Bridger, 1958) were the main types of 

 gear used. 



Larvae collected in the Chesapeake Bight 

 by the Sandy Hook Sport Fisheries Marine 

 Laboratory in New Jersey were examined also. 

 The specimens were taken with Gulf V high 

 speed plankton samplers (Arnold, 1959) dur- 

 ing an offshore survey ranging from Martha's 



Figure \. — Stations sampled by the RV Pathfinder of 

 the Virginia Institute of Marine Science during three series 

 of Atlantic plankton cruises from 1959 to 1963. The 37-m 

 (20-fm) and 183-m (100-fm) depth contours are empha- 

 sized. 



Vineyard, Mass., to Cape Lookout, N.C. The 

 survey consisted of eight cruises made from 

 December 1965 to December 1966. Clark et al. 

 (1969) give details of the survey area and 

 sampling procedures. 



Additional larvae were collected in Norfolk 

 Canyon (approximately lat. 37°04'N, long. 

 74°40'W), 13-14 August 1969, by VIMS per- 

 sonnel on board the National Marine Fisheries 

 Service RV Albatross IV. Four plankton tows, 

 each 1 h long, were made at 6-h intervals. 

 Each tow consisted of four Miller plankton 

 samplers (Miller, 1961), a pair of 0.2-m bongos 

 (McGowan and Brown, 1966), all without 

 closing mechanisms, and a 2-foot Braincon 

 depressor. Estimated fishing depths for the 

 Miller samplers were 2, 50, 100 and 275 m for 

 each tow. The bongos fished at nearly the same 

 depth as the deepest Miller sampler. 



Juvenile and adult specimens were examined 

 from various trawl collections taken between 

 Cape Cod and Cape Hatteras by VIMS or by 

 the National Marine Fisheries Service Labor- 

 atory at Woods Hole, Mass. 



Measurements 



Measurements were made on 100 unstained 

 larvae of each species with an ocular microm- 

 eter and on 100 unstained adults of each 

 species with dividers and a wooden millimeter 

 scale. The larvae were selected from the VIMS 

 1962 plankton collections to represent the 

 available size range. The adults were taken 

 from trawl collections made from 1954 to 1967 

 (mostly 1965-67) between lat. 35°58'N and 

 40°09'N. Lengths reported in this study refer 

 to standard length (SL). Fish were measured 

 with the left side uppermost. The following 

 body measurements, some of which were mod- 

 ified from Hubbs and Lagler (1958), were made: 



Standard length - snout tip to notochord tip 

 preceding development of caudal fin, then 

 to end of hypural plate. 



Head length - snout tip to anterior edge of 

 cleithrum where it meets posterior oper- 

 cular edge (larvae) or to posteromost 

 margin of opercular membrane (juveniles 

 and adults). 



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