10 OKHAMANDAL MARINE ZOOLOGY REPORT 



tide-washed fringing plateau wherever the sea is margined by bard strata. (Plates III. 

 and V.) 



The dearth of life over this littoral plateau is extraordinary ; nowhere else have I 

 seen so bare ail expanse of sea-washed rock. Scarcely a limpet is to be found, and 

 seaweeds are few and inconspicuous. Only here and there in a pool exceptionally 

 well protected do some forms of life flourish. (Plate VI.) 



Beyond low-tide level, along the rocky portions of the coast, the littoral is 

 margined by a considerable width of sea-worn, rounded boulders, torn originally from the 

 coast cliffs, and rolled about on the littoral plateau till at last they have found their 

 way to a depth where they suffer little disturbance. Among these boulders I found 

 considerable wealth of life at the time of my visit (December-January), when they were 

 swathed in a dense growth of seaweeds of several species. I was told that towards or 

 at the onset of the south-weot monsoon, this growth dies down. Anyway, with weed 

 of such density it is a practical impossibility for divers to exercise selection in what 

 they pick up, and to find oysters even if they were there is not possible. It would 

 be even as looking for a needle in the proverbial bundle of straw. Besides this, work 

 by naked divers during the winter season is not commercially practicable on account of 

 the coldness of air and water the air more especially, as the men feel the chilliness of 

 the air most acutely during the intervals between diving. Even lusty Arabs will not 

 face the hardships of pearl-diving in the winter season in the Persian Gulf; so we may 

 at once rule out the possibility of carrying on a fishery by means of naked divers on 

 the west coast of Okha during the cold months of the north-east monsoon. The 

 violence of the sea during the rest of the year the warm mouths when pearling goes 

 on merrily in the quieter waters of the Persian Gulf with even greater force precludes 

 pearl-fishing operations on the ocean coast of Okha at that season. 



With naked divers ruled out, the only alternatives, and those too, available 

 only during the north-east monsoon, are fishing by mechanical means (dredging), and 

 by divers with diving suits and pumps. Neither is feasible, the former by reason of 

 the unevenness of the ground, and the latter partly for the same reason, and partly 

 because of the smothering growth of seaweeds. 



I am satisfied that if oysters did exist in quantity on this rough and uneven 

 bottom, very great difficulties would be experienced in fishing them. I am, however, 

 equally satisfied that pearl oysters do not and cannot exist in this particular locality in 

 any number sufficient to make them worth a search. The bottom is too rugged to suit 

 pearl oysters, which, except in such an unusual instance as the sheltered Jamnagar 

 reefs, require fairly level bottom if we hope to find them in really paying quantities, 

 i.e., in aggregated masses or "beds," in contradistinction to the isolated habit 

 characteristic of the Kutch or Jamnagar pearl oysters. (Note. As will be seen further 

 on, the Kutch pearl oyster is the same species as that of Ceylon, being the small thin- 

 shelled Margaritifera vulgaris, which is normally or typically gregarious.) 



