on any single, panel. They occurred on all except one of the 55 test 

 panels, "being atsent In only one panel at the start of a new series. 

 The attiack rated slight in 19^5 and merely a trace in 1946 and 19^4-7. 



h. U5NS-2 (Pier Wo. 9l ). Limnoria occurred irregularly 

 on 17 of the 55 control panels, the maYimnTn number of tuone^ls "being only 

 h^ cm any panel. They occuired on 52 of the k2 test panels, "being a"bsent 

 on all the group of 8 su"binerged in August and removed in Octo'ber and 

 Hoveiaber 1955. The attack rated slight in 1945 and only a trace in 1946 

 and 1947. 



A56.04 Fouling Agents 



1. Silt . Silt occurred on all the panels of "both the control 

 aiid test series. The deposits ranged from traces to light on the con- 

 trol panels and from traces to moderate, and sometimes oily, on the test 

 panels. 



2. Algae . A trace of a green alga occurred on a single test 

 panel at Pier No. 90. 



5. Inverte"brate animal phyla . 



a. Coelenterata (hydJolds ). Bydroids occurred on 15 of the 

 55 control panels and on 50 of the 55 test panels at Pier Ho." 90, and on 

 10 of the 55 control panels and on 57 of the 42 test panels at Pier No. 

 91. The growths rated as traces on the panels of the' control series, and 

 as traces, or rarely light, on the panels of the test series. Tu"bularia 

 was the only form identified. 



"b. Bryozoa (encrusting and f ilajasmtous ) . Sacmsting Bryozoa 

 occurred more or less ahundantly on the panels at hoth locations. At 

 Pier No. 90 they were on 28 of the 55 test panels, and at Pier No. 91 

 they occurred on 4 of the 55 control panels and on 28 of the. 42 test 

 panels. Cheilopofina praelcaaga , Crl'billna sp., Cryptosula sp., Electra 

 sp., Lichenopora sp., Schizoparella unicornis , Schizoporella^ sp., and 

 Tegella unicornis were identified. Filamentous Bryozoa occurred more 

 or less a"bundantly on some of the test panels at "both locations. At 

 Pier No. 90 they occurred on 9 of the 55 test panels, and at Pier No. 91 

 they occurred on a single control panel and on 6 of the 42 test panels. 

 Bugula flahellaia and Bugula sp. were identified. 



c. Annelida (annelid worms ). Serpulld ( Serpula ) tubes 

 occurred on a single control panel and on 15 of the 55 test panels at 

 Pier No. 90, while at Pier No. 91 they occurred on only 2 test panels. 

 The' number on any one panel was small in most cases, "but 500 worms were 

 recorded cm one of the test panels at Pier No. 90. 



d. Arthropoda (crustaceans ). Balanas ("barnacles) occurred 

 with considera"ble frequency and in great a"bundance on the panels at "both 

 locations. At Pier No. 90 they occurred on 11 of the 55 control panels 

 and on 24 of the sajne number of test panels, attaining a ma.xlmam 



160 



