DESCRIPTION OF THE PEARL-OYSTER BANKS OF THE GULF OF MANAAR. Ill 



parts of the area from 1\ to 13 fathoms, hut the greater part of it is ahout 9|- to 10 

 fathoms. 



The bottom is a few inches ol coarse quartz sand covering flat rock. The sand has 

 ridges ahout 2 feet apart, and has plenty of small " culch," chiefly shells, lying in the 

 hollows. In other parts the rock is exposed and covered with abundance of Padina 

 and other Algae, also Nullipore balls (Lithothamuion fruticulosum). The rock is, in 

 the northern part, a fine grained calcareous sandstone much incrusted with Polyzoa, 

 while further south it is a looser, more porous calcrete of a whiter colour. 



Amonost the common animals found were : 



Axinetta donnani, Spongionella nigra, Petrosia testudinaria, pink and white 

 mottled Pennatulids, Heteropsammia, Astrseids and Turhinaria, Eunicid worms, 

 Linckia sp., Cassis, Pectunculus, Area, Chama, Venus and other shells, Labrus, 

 Batistes, Gobies and other fishes. 



Even where the rock is exposed on this paar it would be suitable for dredging over 

 a matter of great importance, as this is the ground from which the largest supplies 

 of young oysters can be obtained for transplanting to more reliable paars. Some 

 further particulars in regard to this paar will be found in the " Narrative" (p. 76). 



The Southern Paars form for the most part a single series running north and 

 south parallel with the coast from Negombo to Kodramallai. Off Chilaw, however, 

 they become more extensive and allow of division into an outer paar and several 

 inside it. At the northern end, also, off Karativo Island, the plateau widens, and is 

 occupied by the large and important Muttuvaratu and several smaller paars. The 

 chart of the Southern group (fig. 37) shows the paars from Kodramallai Point down to 

 Navakaddua. The few banks remaining to the south of this (Jokkenpiddi, Oolawitti, 

 and those off Chilaw and Negombo) are too distant to be included in the same figure, 

 and scarcely require separate illustration. Their general position can be seen from 

 fig. 1 and fig. 22, in the " Narrative." 



These more southerly paars resemble closely in character the Periya Paar on the 

 outside of the northern group. They are stretches of sea-bottom wherethe under- 

 lying calcrete or modern rock comes to the surface at intervals, or where loose 

 fragments lumps of calcrete, Nullipore balls, and dead shells lie upon the surface, 

 forming natural " culch " to which oyster spat can become attached. The exact con- 

 ditions vary at different points along the coast, and, as might be expected, there are 

 local differences noticeable in the fauna of the paars, which is affected by such factors 

 as differences in depth, degree of exposure, and proximity to inlets of fresh water. 



Dutch Mo drag am Paar. 



This lies 10 miles due west of Kodramallai Point and about 10 miles south-west 

 of the North and South Modragams, and due north from Karativo Paar. It is 

 1^ miles in diameter, and varies in depth from 8 to 14 fathoms. 



