1915O Fauna of the Chilka Lake : Coelenterates. 95 



part of the width of the mesentery (fig. 7 A, p. 94). A little lower down these latter 

 structures become much thinner and weaker, practically disappearing at the lower 

 end of the stomodaeum, while the parietal muscles become better developed. Below 

 the stomodaeum the muscle-banners again become large. The mesogloea in the 

 basal part of each mesentery is thrown on each side into five or six folds, all of 

 which are moderately stout and have an approximately similar form and depth. 



The gonads are normal and the animal is apparently dioecious. 



Our largest specimen of this species is about 30 mm. long in a fully extended 

 condition, the greatest transverse diameter of the scaphus being 3 mm. and the 

 length of the tentacles 6-5 mm., but this specimen is unusually large. 



Types.— No. Z.E.V. 6819/7, Ind. Mus. 



The most important specific characters of Edwardsia tinctrix lie in the shape and 

 colouration of the column, the presence, peculiar structure and comparatively large 

 size of the tubercles on the scaphus, the relative length of the sulco-lateral rudimentary 

 mesenteries, the form and relative size of the longitudinal muscles of the mesenteries 

 and the proportions of the stomodaeum ; but in the identification of specimens of the 

 genus attention must be paid to the general sum of characters rather than to sepa- 

 rate features or to single organs or parts. Perhaps the most peculiar feature of the 

 Chilka species is the structure and size of the tubercles, but those of E. claparedi 

 (Panceri) are probably similar, if relatively smaller, for the nematocysts in these 

 organs are very liable to disappear from sections.' 



E. tinctrix is, for the greater part of the year, one of the most abundant mem- 

 bers of the fauna of the main area of the Chilka Lake, over the whole of which it 

 occurs from the shore to a depth of 16 feet ; in the muddy parts of the outer chan- 

 nel it is much less common. It was found in water of which the specific gravity 

 varied from that of the Bay of Bengal at the time to that of pure fresh water. 

 Outside the Chilka Lake it has not yet been discovered. 



The anemone lives buried in mud as far as the base of the disk. It is extremely 

 shy and sensitive. When removed from mud individuals almost invariably have 

 the disk and capitulum introverted into the scaphus, and it was not found possible 

 to cause them to expand by daylight. If planted in mud covered with water in a 

 glass they often did so by night 2 , but even then showed no tendency to shift their 

 position or to construct fresh burrows for themselves. 



E. tinctrix is much less common in the Chilka Lake at the end of the rains than 

 at other seasons, but a few individuals were found even in November. They were 

 much contracted and did not expand in captivity even at night. It is probable, 

 therefore, that they are affected by long-continued residence in fresh water much in 

 the same way as Halianthus limnicola. 



In specimens taken between March and July inclusive the gonads were ripe, as 



1 See Walton and Rees, Journ. Mar. Biol. Ass. Plymouth X,'p. 64, fig. 2, 1913. 



2 Walton and Rees {op. cit., p. 62) found that an individual of E. claparedi (Panceri) at first 

 refused to expand by daylight but after a time did so. 



