322 Marine Microbiology 



Z. raptor taken aseptically, included the filtrate from a total 

 of three to four replicate flasks. Analyses were made of 

 both cellulol) tic activity and tensile strengtli of the cordage. The 

 latter tests consisted of 9 to 12 pieces of cordage. Three pieces 

 of equal length were cut from each five foot loop present in 

 individual flasks. 



While both species exhibited slight cellulolytic activity as 

 early as three to five days following inoculation, extensive activity, 

 i.e., above 1.0 mg RS/ml/24 hour, was not noted until after a 

 growth period of approximately twelve days ( Table 1 ) . The dif- 

 ference in activit}^ of the two seven day samples of Z. raptor may 

 possibly be attributed to different sampling procedures as well as 

 to the different times of inoculation. The seven day sample with 

 over 0.700 mg RS/ml/24 hr was taken from three separate culture' 

 vessels whereas the fraction with rather low activity consisted 

 of a small sample taken aseptically from a single flask. The dif- 

 ferences in RS production of filtrates collected after twelve days 

 may not be significant. Although the twelve day culture of Z. 

 raptor exhibited considerably greater activity than did the thir- 

 teen day culture, this may be due in part to the different time 

 of inoculation of the two cultures. Both the seven and twelve 

 day cultures, inoculated a week after the initial set of inocula- 

 tions, showed greater activity than did cultures of similar age 

 in the earlier test. 



Significant reduction in strength of the infested cordage 

 was evident at five and seven days of growth of Z. xylestrix and 

 Z. raptor respectively (Figs. 3 and 4). Further reduction in 

 strength occurred with increased growth of the fungi. Repeated 

 tests of uninfested cordage gave average readings of from 95 

 to 105 lb. Considerable differences were noted between the 

 minimal and maximal strength readings of the seven to sixteen 

 day tests of Z. raptor and the five to fourteen day tests of Z. 

 xylestrix. However, in the 20 day test of Z. raptor and the fifteen 

 and eighteen day test of Z. xi/Jestrix, considerably less variation 

 between minimal and maximal readings was apparent. Variation 

 between tests occurred frequently as noted by the results of the 

 fourteen day test of Z. xylestrix. This particular sample showed 



