2. Llmnorla . A small number of Llmnorla occurred in ill- of the 

 kO control panels "but only in those panels suhmerged "between April I9 

 and December 19. The numher in any one panel ranged from one to 25. 

 Limnoria occurred in 28 of the kO test panels. The attack, however, never 

 rated more than a trace except late in 19^7^ when it rose to slight. 



AS.Oif Fouling Agents 



1. Silt . Silt occurred on all except 2 of the IfO control panels 

 and on all except one of the same number of the test panelB. The deposits 

 ranged from traces to light on the control panels and from traces to 

 moderate on the test panels, they vere even heavy and oily on one of each 

 removed Septemher 10, 19^5* 



2. Algae . A trace of green algae was recorded on a single panel 

 each of the control and test series removed on June I9, 19^7? after one 

 and k months* sulmergence, respectively. 



5. Invertebrate animal phyla . 



a. Coelenterata (hydroids ). Hydroids occurred on 29 of the 

 kO control panels and on all except one of the same number of test panels, 

 the growths ranging from traces to light on the controls and from traces 

 to moderate on the test panels. The forms identified comprised Tubularia 

 most freq^uently, and also Pennaria tl are 11a . 



Id. Bryozoa (encrusting and filamentous ). Encrusting Bryozoa 

 occurred more or less abundantly on 5 control panels and on 8 

 test panels. The forms identified included Cryptosula pallaslana 

 and Schizoporella unicornis . Filamentous Bryozoa occuixed, mostly in 

 fairly small numbers, on 5 control panels and on k test panels. 

 Bugula sp. was the only form identified. 



c. Ar thropoda ( crus taceans ) . Balanus ('bamacles) occurred 

 on 6 control panels, where diameters up to 6 iQm"were recorded, and on 



22 test panels, where diameters up to 17 mm were recorded after submergence 

 for k montlis. One of the control panels weis 25^ covered, and k 

 consecutive test panels removed at monthly intervals from August I9 to 

 Novemher I9, 19^6, after having "been su"hmerged for k months, were from 

 25?o to 50^ covered. Anrphipods ( Corophium ) occurred on 2 control panels 

 and on 6 teat panels, the numher on the latter ranging fronl 25 to 25O. 



d. Mollusca (nonhoring molluaks ). Miscellaneous mollusks 

 occurred sporadically on occasional , panels . Ten specimens of Anomia 

 (jingle -she lis) up to 6 mm in diameter occurred on a single test panel 

 submerged for 5 months. A few specimens of Mytilus (mussels) occurred 

 on 2 of the test panels, with lengths up to 18 mm recorded after suh- 

 mergence of k months . 



1*8 



