112 



nine months. Accordingly I had the largest specimen of 

 Montipora carefully detached from the dead coral-rock on 

 which it was growing, and found that it measured 40 inches 

 in length, 9 inches in height, and 16 inches in breadth, and 

 weighed 17 pouads. 



After remaining at anchor for some days off Silavaturai, 

 we started on the morning of the 10th for the western side 

 of the great Cheval Par, which is known by the divers as 

 kodai (umbrella) Par from the prevalence on it of a shallow 

 cup-shaped sponge, Spongionella holdsworthi, which is sup- 

 posed, by their imaginative brains, to resemble an umbrella. 

 In a letter to Mr. Bowerbank, by whom this sponge was 

 described,^ Mr. Holdsworth stated that " is onl}' found on 

 the 9 fathom line of the large pearl bank. It is attached to 

 pieces of dead coral or stones. When alive it is of a dark 

 brown ; and when taken out of water it looks exactly like 

 dirty wet leather .... This sponge is so strictly confined 

 to the locality above mentioned that its discovery by the 

 divers is considered the strongest evidence that the outer 

 part of the bank has been reached." Another conspicuous 

 sponge on this bank was the large, pale pink-coloured 

 Petrosia testudinaria, which also lives on the Tholayiram 

 Par. 



It was from the Cheval Par that, in 1888, about 150 

 millions of oysters, ripe for fishing, disappeared in the space 

 of two months, between November and February. This 

 disappearance en masse was attributed by the natives to a 

 vast shoal of rays, called 8ankoody ti/rica or Koopu tyricay 

 which is said to eat up oyster shells. But the more prac- 

 tical mind of the Inspector of the pearl banks attributed the 

 disaster — for such it was from a financial point of view — to 

 the influence of a strong southerly current, which was running 

 for some days in December — a current so strong that the 

 Engineer of the Active had to let go a second anchor to 

 prevent the ship from dragging. 



The divers, going down from the ship as soon as we 

 were at anchor over the bank in 6i fathoms, reported abund- 

 ance of young oysters, whose average breadth at the hinge 

 was '75 inch, said by some to be three months, by others six 

 months' old, and brought up samples, from the rocky bottom 

 interspersed with patches of fine sand, attached to dead coral, 



' Froc. Zool. Soc, 1873, p. 25, pi. v. 



