42 



The rocky ground was flat-surfaced and largely continuous ; the sand}' stretches 

 found on and between the pars was never deep, scarcely ever exceeding a depth of 3 

 inches, and in consequence, individuals of the large species of Piuua, which is here 

 characteristically abundant, are exposed for fully live-sixths of their length, only the 

 apex being embedded in the sand. Quite a large proportion were dead shells. 



Crowds of large Barnacles {Balanus sp.) aud Zoophytes occupy the outer surfaces 

 of the valves as well of the living as of the dead, the cavities of those barnacles that 

 are dead harbouring great numbers of small crustaceans and worms. 



A favourable feature of these pars is the absence of an excessive amount of 

 sponges. Such as there were of the larger forms consisted principally of the massive 

 Suberites ineonstans and the cavernous Siphonoclialina communis. In the former, 

 besides the usual species of Gebia, were several of an interesting heteronereid form of 

 Nereis. The tall, branched tubes of Eunice lubifex were met with wherever rock 

 appeared on the surface. 



A characteristic organism is a Botrylloides sp. which forms grey gristly-looking 

 rounded masses of 3 to 4 inches in diameter. Algae were scant in quantity. 



The depth of the water over these pars shows great regularity, ranging within 

 the limits of half a fathom, 6 to 6| fathoms. 



The only signs of pearl oysters consisted of occasional dead valves, old and much 

 corroded and of an age which I would fix approximately at 2~ years. They had the 

 appearance of having been dead several years. 



A few chanks were found on the sand outside the eastern margin of the pars, 

 where the sand is fine and largely calcareous in composition. 



From 9-r>0 to 11-15 a.m. an oily calm prevailed, the surface of the sea covered 

 as far as the eye could see with a brown scum composed of Trichodesmium erythrceum. 

 Its appearance and to some extent its effects were such as a thin film of oil produces 

 when spread upon water. 



We remained at anchor till the next morning near the middle of the Cruxian 

 Par. A strong southerly swell prevailed the whole night and as a land wind blew 

 with some force from the N.W. the ship rolled heavily making sleep practically 

 impossible. 



At 7 a.m. on May 11th we proceeded northwards after casting off the four inspec- 

 tion boats, which were ordered to examine the ground lying between the Cruxian Par 

 and the most southerly of the next group to be examined — the Marikan Par group — 

 and then to pass northwards over the whole extent of the latter pars. 



The steamer led the way dropping a mark buoy on what was believed to be the 

 south side of the Padutta Marikan Tundu Par, as a guide to the following boats. We 

 then headed north and anchored on the Devi Par. 



The boats reported continuous sand after passing the northern edge of the 

 Cruxian Par, both between the two groups and along the line which should have led 

 them over the Marikan Par group of banks — an unsatisfactory result due either to the 

 plotting of the cross-bearings being incorrect or to the pars being incorrectly placed 

 upon the chart. I incline to believe that the former explanation is the true one, 

 seeing that the Inspector, although the shore-marks are distinct and clearly visible, 

 has not the position of these marks indicated upon his chart. Eough and inexact 

 work is the inevitable consequence. 



Vaipar Karai Pae. — The next day, May 11th, after ascertaining that the ground 

 in 6| fathoms, two miles east of outer Chullai Island, consisted of fine sand mixed with 

 a considerable amount of mud, we proceeded towards the south-east and anchored 

 upon Vaipar Karai Par in 6| fathoms in order that I might make a descent in the 

 diving dress. 



When I alighted upon the bottom I found the water so turbid with suspended 

 mud particles that it was impossible to ascertain what lay underfoot save by crawling 

 on hands and knees, and even then I had to bring the helmet window within two 

 inches of the ground. By so doing I found the bottom to be composed of fine calcare- 

 ous sand commingled with a considerable proportion of muddy sediment. The surface 

 was littered with numerous dead pearl oyster shells both entire and fragmentary, and 



