on 2 coatrol panels and k test panels of the lower "board at the Depexming 

 Station; on k control panels and 2 test panels of the upper l>oard at the 

 Depermlng Station; ana on 10 control panels and one test panel of the test 

 hoard at the Custom House Pier. Electra crustulenta and Electra sp. were 

 the onl7 forms identified. A trace of filamentous Bryozoa was recorded en 

 a single control panel of the lower hoard at the Ddpermlng Station. 



c, Annelida (marine worms) . Traces of serpulid ( Serpula ) 

 worms occurred on a single test panel of the lower test hoard at Pier 

 317-C; on 5 panels of the lower test hoard at the Depermlng Station; and 

 on 7 test panels of the test hoard at the dust am House Pier. The maxlnium 

 number on any one of the latter was 2^ and the mfljclmmn length attained 

 was 1^ mm. 



d, Arthropoda (crustaceans ). Balanus (hamacles) developed 

 profusely and with great regularity at all five locations, occurring on 

 nearly all the control panels at each location, and on all except one of 

 the test panels. They developed on the control panels during every 

 calendar month of the year, attaining maylmam diameters of 'J, 8, 11, 8, 

 and 8 mm, respectively, on the control panels of the five different test 

 hoards, in the order named. On the test panels they attained maxlnnnn 

 diameters of 1^, 1?, 22, l8, and 23 mm on the different test hoards, 

 respectively. Prom 15 to 25 control panels and from 23 to 39 test panels 

 of the 5 test hoards, respectively, showed from 50^ to lOCfji of the surface 

 covered, Ang)hipods (including Corophium and Gammarus ) occurred sporadi- 

 cally at all five locaticaas. They occurred on 6 control paneis and one 

 test panel of the lower test hoard at Pier 317-C; on 3 control panels 



and lii- test panels of the upper test hoard at this Pier; on 8 control 

 panels and 15 test panels of the lower test hoard at the Deperming Station; 

 on 11 control panels and ik test panels of the upper test hoard at this 

 Station; and on 7 control panels and 9 test panels of the test hoard at 

 the Custom House Pier. The greatest number recorded on any one panel 

 was 600. 



e, Mollusca (ncnhoring molluBks ). Miscellaneous mollusks 

 occurred sporadically on the panels of the test hoards at all five loca- 

 tiooa. %tilus (niasBels) occurred on a single control panel of the 

 lower test hoard at Pier 317-C; on one each of the control and teat seirLes 

 of the upper test hoard at this Pier; on 2 control panels and ik test 

 panels of the lower test hoard at the Depermlng Station; on 2 control 

 panels and k test panels of the upper test hoard at this Station; and on 

 10 test panels at the Custom House Pier. In most cases the numbers were 

 few, hut as many as 1,500 were recorded on a single test panel of the 

 lower test hoard at the Depermlng Station, Maximum lengths of l^l- mm 



on a control panel, and of l8 mm on a test panel, were recorded. 



73 



