were 30^ to 90^ covered, and maximum diameters of Ik mm were recorded on 

 panels submerged for 5, k, and 5 months, respectively. At the Operating 

 Facility, barnacles occurred sporadically on 5 of the 11 control pemels 

 and on 7 of the 11 test panels, tut they were few in number. Maximum 

 diameters of 9 mm were recorded on a control' panel ajid 17 mm. on a test 

 panel*, which had "been removed after two months' submergence. 



f, Mollusca (nonboring mollusks ). Miscellaneous mollusks, 

 which occurred occasionally (limited f=tlTnost entirely to the Air Facility), 

 were ae follows: Anomia (jingle-shells) occurred on k each of the control 

 and test panels at the Air Facility. Maximum diameters of 9 ma were 

 recorded on a control panel and 20 mm on e test panel, after having "been 

 submerged for k- months. Mytilus (mussels) occxirred on a single control 

 panel and on 5 test panels at the Air Facility. A trace of Ostrea (oysters) 

 occurred on 5 test panels at the Air Facility. A trace of Pinctada 

 radiata occurred on 2 test panels at each location. A solitary specimen 



of Pecten (scallops) occurred on a single test panel at the Air Facility. 



g, Chordata (tunicates ). Tunicates were recorded on the last 

 5 of the 11 test panels at the Air Facility. Only 5 to 20 colonies 



were recorded on any one panel. Botryllus s Chios seri was identified on 

 each panel, though other unidentified tunicates were present. At the 

 Operating Facility, Botryllus schlosseri occurred on 5 ot the control 

 panels and on a single test panel, tdie number, of colonies on any one peinel 

 ranging from 3 to 10. 



A27,05 Stnmnfiry and Conclusions 



1. Installation . Test boards of the panel type were operated from 

 June 19hh to June 19h^ at the U. S. Naval Air Facility and U. S. Naval 

 Operating Facility located at Bahia, Brazil, about 12 miles apart by water, 

 to determine the Identity and prevalence of marine borers and fouling 

 organisms at these locations. 



2, Test Eesults . 



a* Borers . Teredlnldae were very active each year at both 

 these locations, the breeding season being continuous. The attacks rated 

 veiy heavy at both locations in 19M«- and 19^5 » panels becoming filled or 

 riddled within 2 months at the Air Facility and in k months at the Operating 

 Facility. Increasing the thickness of the panels to 2 inches failed to 

 prolong their life, the attack being Just as severe proportionately in the 

 thicker panels as it was in the thinner ones. Limnoria occurred to a 

 slight extent at both locations, the attack rating zero in 19kk and only 

 a trace in 19l^5 at the Air Facility, while at the Operating Facility it 

 rated slight both years. Pholadidae also were active to some extent at 

 both locations, the attack at the Air Facility" rating zero in 19^ and 

 moderate in 19^5, while that at the Operating Facility rated slight both 

 years. 



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