A^^'O'i Marine Borers 



1. Teredinldae . Teredlnidae ( Bankla setacea ) were more or less 

 active at this location throughout the period of the test. In the control 

 panels, only 2 embryonic specimens occurred, and these specimens were in 

 the panel submerged from July l6, 19^5* They occ\xrred in 12 of the l6 test 

 panels, attaining a maximum length of 290 mm in 8 months. Six, of the 

 panels were from 25^ to lOC^ filled in this time. The breeding season 



at this location can not be exactly determined from the brief test because 

 of the extremely limited occxirrence of Teredinldae in the control panels, 

 but considering their occurrence in the" test panels, it appears to extend 

 from February to at least the middle of July. The attack rated very heavy 

 in 19^5 aiid medium heavy in 19^6. 



2. Llmnoria . Limnorla were active at this location throughout 

 the dxiration of the test. They occurred in all except one of the control 

 panels, the maximtrai number being 850 in any one panel. They occurred in 

 every one of the test panels. From the time the test board was submerged 

 late in 19^^ there was a rapid Increase in the Llmnoria popiilatlon, which 

 attained a peak rating of very heavy in the panel removed on July I6, 19^5^ 

 after 8 months' submergence. After reaching the peak rating, the attack 

 subsided somewhat, but again attained a peak rating of very heavy in the 

 8-month panel removed on January 15, 19^6. It again subsided noticeably, 

 but attained a rating of medl\m heavy in the panel removed on August 16, 

 19^6, when the operation of the test board was discontinued. 



A3U.04 Fouling Agents 



1. Silt . Silt occurred as traces on I6 of the 21 control panels 

 and as traces to occasionally light deposits on all of the 21 test panels. 



2. Algae. Algae occurred on only one control panel emd on 11 

 of the 21 test panels. The growths were mostly traces but were light 

 occasionally. Most of these forms were green algae, but red and brown 

 algae also occurred. 



3« Invertfebrate animal phyla . 



a. Coelenterata (hydrolds ) . Hydroids occurred as traces on 

 8 control panels and on I5 test panels. 



b. Bryozoa (encrusting and filamentous) . Encrusting Bryozoa 

 occurred on 5 control panels and on I7 test panels . Cribillna annulata, 

 CryptoBula pallaslana , Electra monostachys , ELectr'a sp. , Tegella ujiicornls , 

 and^ a member of l;he Alderinidae were identified. 



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