c. Annelida (annelid vorms ). Serpulid ( Senaula ) ■vrorms 

 were recorded on only one test panel which showed 15 to 20 specimens up 

 to 10 mm long. 



d. Arthropoda (crustaceans ). Balanus (barnacles) occurred 

 with great regularity and often in oonsideratle abundance. They were 

 recorded on l6 of the 19 control panels, and on all the test panels, and 

 developed throughout the year. In the control panels, the maximum 

 diameter recorded was 7 mm, and panels exposed in February and March 



of 19^i)-. were 100?^ covered. In the test panels, the maximum diameter 

 recorded was 22 mm, this appeeiring on a panel removed January 30, 19^5^ 

 after having been submerged for 5 months. The rate of growth and 

 nximber present appeared to vary considerably In the same month during 

 different years. 



e. Mollusca (nonborlng mollusks ). A trace of Ostrea (oysters) 

 occurred on one control panel and on k test pginels, the greatest 



number recorded on any panel being 5« Anomla (jingle- shells) occurred 

 on k control panels (second, third, and last two), where the ma.YlTinim 

 number on any one was 55 » and on 5 test panels (third amd last two), 

 where 60 was the maTiTnuTn number. 



f. Chorda ta (tunloates ). A few colonies of Botryllus 

 schlosseri occurred on only the first of the test and control panels. 



A20 . 05 SuTttmary and Conclusions 



1. Installation . A test board of the panel type was operated 

 at the IT. S. Naval Frontier Base at Galveston, Texas, from July 21, 19^^ ^ 

 until its discontinuance on July 15* 19^6, to determine the identity 



and prevalence of marine borers and fouling agents at this location. 



2. Test Results . 



a. Borers . Teredinldae were more or less active throughout 

 practically the dxiration of the test, the severity of the attack rating 

 very heavy, emd panels frequently becoming riddled after 5 months' ex- 

 posure. The attack at this location was so severe that the period of 

 exposure of the test panels was reduced from 8 to 1; months. Th6 

 breeding season extended from March through December. Limnorla were 

 present in small numbers throughout the test, but they never exceeded 



a trace most of the time, though they did become low in the rating of 

 slight in 19^5. Only a trace of Pholads was recorded at this location. 



b. Fouling jOrKanlsma . Silt, algae, and Invertebrate 

 anlmala belonging to 6 phyla contributed to the fouling of the panels. 

 The latter were comprised df hydroids, encrusting Bryozoa, annelid 

 wonns, barnacles, oysters and Jingle-shells, and tunloates. Silt, 

 hydroids, and barnacles occurred with great regularity, the latter being 

 the most important organism causing fouling. The encrusting 



Bryozoa occurred less frequently, while the other forms occurred only 

 occasionally. 



98 



