t. Finder Pier Ho. 21 . Teredlnidae occurred In 8 of the 

 52 control pemels, but there were none in the panels removed from 

 Septeniber 21, 19l;4 to May 25, 19^7, with the exception of the panel 

 su'bmerged from September 5 "to October 9> 19^6. They ranged from minute 

 pits to specimens up to 42 mm in length. The "breeding season at this 

 location appeared to extend from the middle of May through October. 

 Teredinidae occurred in 16 of the 52 test panels and again none occurred in 

 the panels removed from Septemher 21, 19^; to Septanber 5> 19^6, hut they 

 did occur in every pajael thereafter. A maximum length of 520 mm (about 

 15 inches) was recorded in a panel submerged for 9 months. The last 

 2 of these panels were filled. At this location there was no attack 

 in 19^5; the attack in 19l|-6 rated moderate; and in 19^7, very heavy. 



c, Hiaval Ammunition Depot Pier . Teredinidae occurred in 

 6 of the 52 control panels here, but there were none in the panels removed 

 frcaa October 25, 19^ "to May 25; 19^7 > except in the panel submerged 

 from September 5 to October 9j 19^6. The specimens ranged from minute 

 pits to individuals up to 25 mm in length. The breeding season 

 appeared to extend from the middle of May through October. Teredinidae 

 occurred in 25 of the 55 test panels, with a maximum length of 155 ram 

 recorded on one panel submerged for 8 months. Six consecutive panels 

 removed from late 19M«- to early 19^5 were riddled, and one panel taken out 

 in 1914-7 was filled. The attack at this location rated very heavy in l^kk and 

 19^5* moderate in 19^6, and very heavy in 19i»-7. 



2. LjBinoria . No evidence of Limnorla occurred in either the 

 control or test panels at any of the three locations. 



Al^O.Ol^• Fouling .Agents 



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

 control panels at Shipbuilding Ways No. 8. The deposits, in general, 

 ranged from traces to light or rarely moderate on the panels of the 

 control series and from light to moderate on the panels of the test 

 series, 



2. Algae . Traces of green algae appeared on a single panel of 

 each of the control and test series at Shipbuilding Ways No. 8. 



5. Invertebrate wri-tTnai phyla . 



a. Ooelenterata (hydroids ). Hydroids occurred with great 

 frequency on the panels at all locations. They were on 25 of the 57 

 control panels and 56 of the 58 test panels at Shipbuilding Ways 

 No. 8 on Ik of the 52 control panels and 27 of the 52 test panels at 



179 



