144 Natural History Bulletin. 



top of this polyp will be seen to be below that of the outer 

 calicular lobe. All that the polyps of this species seem to be 

 able to accomplish in the way of retraction is to draw the gul- 

 let within the calicle, fold the tips of the tentacles over the 

 mouth and hide behind the outer lobe of the calicle. (See 

 figs. 2 and 7, PL VIII.) 



As might be expected these polyps, being exposed to greater 

 dangers than those of preceding species on account of being 

 unable to seek the protection of the interior of the calicles, are 

 provided with a means of protection not heretofore encoun- 

 tered in the species described. The tentacles and body walls 

 are provided with an external armor of small spicules and are 

 thus enabled to hold their own in competition with completely 

 retractile forms. 



So far as I can ascertain it is a general rule among Alcy- 

 onaria, or at least AlcyonidcB and Gorp^onidcB^ that the polyps 

 are provided with spicules in direct ratio to their inability to 

 retract witliin their calicles. 



The color of the polyps is a light grey, conspicuously lighter 

 than the general color of zoanthodeme. 



The tentacles are short and tapering, the papillae not so 

 numerous as usual, being reduced to from 5 to 8 on each side 

 of each tentacle near its tip (PI. VIII, fig. 5). These papillae 

 are hardly more than knobs and are doubtless much restricted 

 in their movements, if they are mobile, by the spicules which 

 encrust both tentacles and papillse. 



In the figure giving oral view of folded tentacles, PI. VIII, 

 fig. 3, it will be seen that they are so disposed that the tips of 

 three only are unprotected, the remaining five being neatly 

 tucked away out of sight and presumably out of danger. 



In living specimens of this species there is far less motion 

 of the tentacles than in any of the others studied. I also failed' 

 to find any indication that the ectodermal investment of the 

 tentacles was ciliated. 



Z'/^c^^?^//^/ appears to have a larger cavity and fewer con- 

 volutions than in other polyps of similar size. This is doubt- 



