47 



an amorphous mass composed of their corpses at the bottom 

 of mj collecting glasses. It is, in fact, essential for the pre- 

 servation of many of the gelatinous surface organisms that 

 they should, in this country, in the absence of an apparatus 

 by which they can be supplied with a constant stream of cool 

 water, be at once treated with the necessary fixing and 

 preservative re-agents ; but the management of the requi- 

 site processes is by no means an easy matter in the limited 

 space afforded by a native canoe. The suggestion made by 

 Haeckel that the death and decomposition of the delicate 

 organisms might be prevented by placing them in vessels 

 cooled by ice is, without doubt, an excellent one ; but un- 

 fortunately, ice cannot, as a rule, be procured in out-of-the- 

 way places where one most requires it. 



Among the pelagic organisms which I have collected 

 over the coral reefs in the Gulf of Manaar may be mentioned 

 various small Medusce, Beroe, Cydippe, Bolina (present one 

 morning in such abundance that the net became instantly 

 filled with a thick jelly), dense crowds of Copepod and Schizo- 

 pod crustaceans sometimes rendering the surface of the water 

 milky ; Zocp.a, Phyllosoma, and Alima larvse ; violet-blue Jan- 

 thimv ; and Styliola acicula, a pteropod Mollusc, whose dead 

 glassy shells are very abundant in deposits from the sea 

 bottom. Less fi'equently met with were young Cephalopods, 

 of which the adults, as well as an Annelid [Nereis) obtained 

 by digging deep holes in the sand, are extensively used as 

 bait by the fishermen; Sa/pce; and the ova and young of fishes. 

 Floating, too, on the surface of the water, and conspicuous 

 by their bright colouring, were various Siphonophora — Phy- 

 salia (the Portuguese Man-of-war), Velella with its sun- 

 dial-like crest, and Porpita with its exquisitely marked disc. 

 Many minute pelagic animals were obtained by shaking in a 

 tumbler of water the marine Algce which were floating over 

 or living on the reefs, and of which the most conspicuous were 

 Sargassum vnlgare (Fig 1) and Padina pavonia (peacock's tail). 

 These pelagic organisms, from which the main food-supply of 

 the coral polyps is probably derived, were far more abundant 

 and varied over the Pamban reef during my visit to Rdmes- 

 varam Island in 1886 than in 1888 : and this is probably to 

 be explained by the fact that, in the former year, there was 

 but little wind, and the water was so clear that, in the early 

 morning before the gentle day breeze set in, the individual 

 corals could be clearly distinguished as I rowed over the reef; 



