In an 8-month panel remoTed in May 19^5 • After this, the nxmiber of tunnels 

 fell abruptly and remained fairly low through Octoljer 19^5 > and then 

 suddenly attained a high peak, with never less than 75^ and mostly $0, 

 tunnels per sq in. from then until the termination of the test at the 

 end of Meiy 19k6. The Hmnpria attack thus rated very heavy in "both 19^5 

 and 19^6. 



5. Pholadidae . Wo Pholadidae were recorded at this location. 

 A54.04 Fouling Agents 



1. Silt . Traces of silt occurred on all the panels except 

 one of the controls. On the control panels, there were mostly traces 

 "but sometimes light deposits; while on the test panels, silt mostly- 

 ranged from traces to light, but sometimes moderate, and once heavy. 



2. Invertebrate animal phyla . 



a. For if era (sponges ). Encinsting sponges occurred on 

 9 of the 22 control panels and on 11 of the 22 test panels . On the 

 test panels, it occurred on all except one of those panels removed 

 from November 20, 19Mi- to October 20, 19l»-5. While these painels 

 were mostly limited to occasional colonies, there were as many as 50 

 on a test panel, ajid 2 control panels were recorded as 25^ and 50^ 

 covered, respectively. 



b. Coelenterata (bydroids ). Bydroids occurred on most 



of the panels, but they were absent on the control peinels removed after 

 October 19^5 and also on the test panels removed dviring the months 

 from Decemher 19^5 through April 19^6. They rated as traces on 

 the control panels £ind as traces, hut sometimes light, on the test 

 panels. 



c. Bryozoa (encrusting and filamentous ). Encnisting 

 Bryozoa occurred more or less abundantly on all the control panels 

 eind on all except one test panel. Nine test panels were from 25/^ to 

 80^ covered, eind even one of the control panels was 75^ covered. In 

 most cases, the orgajiiam was identified as Cryptosula pallasiana 



or as Cryptosula sp. , but Hippodina feegeenis and Watersipora cucullata 

 also were identified. Filamentous Bryozoa were recorded on 3 control 

 panels and on 2 test panels, hut mostly as traces. 



d. Annelida (annelid worms ). Serpulid ( Serpula ) tubes 

 occurred more or less abundantly on all but 5 of the 22 control panels 

 and on all of the test panels. One control panel was 5^ covered, and 

 one test panel was 12^ covered. The maximum length of the tubes recorded 

 on the control panels was kO mm, while the TnaYlmum tube length on the 

 test panels was 60 mm. 



251 



