HYDROIDS OF WOODS HOLE. 



373 



CLVTIA VOF.UBILIS. Fig. 4. 



On floating masses of Sargassum were found prolific colonies 

 of a hydroid which had many of the characteristics of Clytia 

 johnstoni, and which I took for a time to be that species, though 

 recognizing certain features which differed from it. During the 

 current summer I took at Harpswell, Maine, what proved to be 

 very typical specimens of the species, and which upon comparison 

 with the former showed very marked and constant differences. 

 I was therefore forced to reconsider its specific relations. In 



FIG. 3. 



doing this I had occasion to compare it with specimens taken at 

 Naples several years ago, and which I had then considered as 

 C. johnstoni. The two species had much in common, indeed 

 differed hardly more than might species from remote localities. 

 A review of the literature brought to light the fact that certain 

 authorities have considered the two above named as identical. 

 For example, in his monograph " Die Hydroiden des k. k. natur- 

 historischen Hofmuseums," Marktanner-Turneretcher has thus 

 treated them, giving preference to the earlier name of Ellis and 

 Solander. 



