X. A PELAGIC vSE A- ANEMONE WITHOUT 

 TENT A CLE vS. 



By N. Annandai^e, D.Sc, Superintendent, Indian Museum. 



During a visit to Puri, on the Orissa coast of the Ba}^ of Bengal, 

 my assistant brought me (on February ist, 1909) a number of small, 

 more or less globular bodies which he had found on the beach at 

 the edge of the waves. A careful search revealed many more. On 

 examination these bodies proved to be Actiniaria in a state of 

 contraction. On being placed in clean sea- water they immediately 

 changed their shape, becoming narrowly conical instead of globu- 

 lar ; but no tentacles appeared. The oral extremity became 

 nearh^ flat, the peristome being distinguished from the column b}^ 

 its greater translucency as well as its position. The mouth was 

 conspicuous, forming a relatively long, narrow slit expanded at one 

 end. The whole animal had a milky appearance, which concealed 

 its internal organs ; the exterior had a pale vinous colour, which 

 deepened into brown at the aboral pole. A circular pore was 

 easily seen at this pole. 



As these Actinians evidently represent a form very different 

 from any previously described, I propose to call them Anactinia 

 pelagica, gen. et sp. nov., in allusion to their lack of tentacles and 

 their pelagic habit. Although none of my specimens have gonads 

 in a recognizable condition, I do not think that they represent a 

 larval stage, for on the one hand the large number of mesenteries 

 they possess, and on the other the fact that man}- Actinians only 

 exhibit sexual activity at certain times of year, is evidence to the 

 contrary. Several forms have, however, been described by van 

 Beneden as larvaj which possess a considerable number of mesen- 

 teries. The following description is based on the dissection and 

 sectioning of a number of specimens as well as on the superficial 

 examination of living and preserved material. 



Structure. 



Column. — The column may be any shape between globular 

 and conical, the aboral end being pointed in the latter case and 

 the peristome nearlj^ flat. These dift'erences in form are due solely 

 to the state of contraction or expansion of the muscles. My largest 

 specimens measured, when full3^ expanded, about 12 mm. in length 

 and 4 mm. in transverse diameter across the peristome, which met 

 the walls of the column practically at a right angle. In such speci- 

 mens the aboral extremity measured onh^ i mm. in diameter, the 



