di;partme:nt of marine biology. 145 



In Gorgonia there is always formed a complete layer of coenenchyma over a 

 denuded area, which remains free from polyps for some time. The ento- 

 dermal canals keep pace with the formation of the other tissues, ^ut it is 

 considerably later that the bud-like swellings of the canal, which mark the 

 points of origin of new polyps, make their appearance. They always follow 

 the same sequence as that shown in the formation of new tissue over a de- 

 nuded area, appearing first at the periphery nearest to the older polyps. The 

 formation of new skeletal tissue at the end of a cut branch takes place very 

 slowly at first. After the new rod of skeletal tissue has attained a diameter 

 equal to that of the older portion the elongation of the branch takes place 

 rapidly. If the living tissue is removed from the skeleton about the base of 

 a colony, there is, so far as my observations show, no down growth of tissue 

 from the cut surface above the denuded stem, 



EFI^ECT OF THF HURRICANE OF OCTOBER IJ, I9IO, ON THE ALCYONARIAN 

 FAUNA ABOUT TORTUGAS. 



The hasty observations made in January 191 1 showed that as a result of 

 the hurricane of the previous October there had been a great destruction of 

 gorgonians on the reefs about Tortugas. On the east shore of Loggerhead 

 Key, the only one visited at this time, many specimens of some five or six 

 species of gorgonians were found thrown up on the beach along its entire 

 length. At that time no estimate of the number cast up was made, nor was 

 the area of reef visited sufficient to give conclusive evidence of the propor- 

 tion of colonies carried from their natural location. In July 191 1 the obser- 

 vations on these points were extended to an extensive area of shore-line and 

 submerged reefs. 



At one point on the inside of the east reef, near Bush Key, the gorgonian 

 skeletons were counted over a strip of beach 112 yards in length, where 

 there was a windrow, perhaps a yard wide, made up of the skeletons. The 

 number of skeletons in a linear yard (practically a square yard) was 75.7 

 as the average for ten counts made at roughly equal distances through the 

 above-mentioned distance, or approximately 8,500 colonies. This area showed 

 very clearly that the most destructive part of the storm came from nearly 

 northeast. On the outside of the reef, in the direction indicated by the wash 

 of the storm, only two living colonies of gorgonians were found for as far 

 ofifshore as the water was sufficiently shallow to allow one to wade about 

 over the reef. Gorgonians were growing abundantly over this area when it 

 was visited in 1910, so the destruction had been almost complete. That the 

 greater number of the colonies found in the windrow on the beach had come 

 from this shallow-water area was shown by the fact that in the deeper water 

 on the outer portion of the reef there was little evidence of the lessening of 

 the number of colonies below the normal number for such locations, where 

 the colonies are ahvays comparatively scattered, never forming dense "thick- 

 ets," as they do on the reefs in shallow water. The very shallow water on 

 the outside of the reef contained a considerable number of skeletons of Gor- 

 gonia Habelhim and Plcxaura Uexuosa, which had been broken off from their 

 supports or carried away f rorn their original location while still attached to a 

 good-sized piece of coral rock. Apparently these specimens had reached 

 their present location at a time when the wave-action had become insufficient 

 to carry them over the crest of the reef on to the beach on the lagoon side. 

 Among the specimens along the beach on the lagoon side of the reef, by far 

 the larger number were still attached to a piece of coral rock, usually one of 

 small size. In almost every instance the skeleton shows that the colony was 



