/\ (•/>(>/'/ s to the Colonial Office. 177 



beds. The rr.ib is also s;iicl to be injurious, cuttinc^ the byssus of the 

 ojsUt. a note is given on j)a<xe ^^ re<^ftr(lin<; an enemy tbiit nitikes a 

 n»un(l hnlc in tlie oyster shell ; this mysterious enemy is one of the 

 curnivurous whelks. 



Evidently, from the report, numerous small mollusca prey on the |)carl 

 oysters. Two fish, t!ie Triirjxer Kish ( /Inh'ftffs rnifis) and skates (Trt/f;on 

 trarnak), also do much harm. On patre Ti it is stated that "the numiTous 

 rock fish which abound on the Arijipu banks feed on oysters . . . the quan- 

 tity devoured by these voracious fish nuist be considerable." Later, it is 

 stjitrd to Ix' useful, as it preys on the injurious Sunin or mussel. Skates of 

 several unknown species are referred to as very destructive. Divers, both 

 KurojH?an and native, f^ive various titles as to the damage done by sea 

 snakes, but nothing authentic is given. 



Floods of fresh, muddy water are stated to be most injurious. 



Little definite seems to be recorded as t(» the age of pearl oy.sters, but 

 it is stated "that oysters may be profitably fished at the age of four years, 

 and that they are in th'ir prime at five years, and may be kept till that 

 age if circumstances permit of it, but if they are kept until the sixth yea 

 they are almost certain to be found dead." The best time to fish then, 

 however, does not appear to be settled. 



The advisal)ility of retaining native divers is entered into at some 

 length, their superiority over the European at this work being clearly 

 pointed out. Their reward is now raised to one-third of the oysters 

 colIectetL Recommenilations to start a chank fishery in the neighbour- 

 hood of the jx'arl banks arc given. One fishery exists north of Maiiaar 

 Islands, about 2,<mm»,(MM» chanks being exported from JatTna to Calcutta. 

 The chanks are u.scd as ornaments by the Hindus. 



The main body of the re])ort (;'.'.) pages) is taken up by eight ap])endices. 

 The first dealing with spat, true and false; enemies of the oyster ; chank 

 fishery ; age of the jiearl oyster and artificial cidture ; being extracts from 

 the report of ilr. Thomas, ^ladras Civil Service, to the Government of 

 Madras, on the Pearl P.anks and Fisheries of Tuticorin. 



The most important pari in this report regarding the true spat is here 

 reproduced : — 



*' The challenged spat in the largest sliell whicli I have seen is 

 \h sixteenths of an inch from hinge to contour R'<-tangularly at its 

 widest p4»int, and the largest drawing in Sir J. Emerson Tenneut's 

 work is no more ; it is, therefore, so small as to need very close 

 examination. Looked at under a hand lens and un(hr a low power 

 microsco|K', I made it out to dilTer from the shell of the |x?arl oyster 

 in l)eing much more convex, more obli(jue ; in having the ear on the 

 short side, not produced in an almost straight line, but roun<lo<l off 

 and tumefl up insteail of l»eing flat ; in bavins: the right valve fitting 

 deeply into the left valve, with the edge of the riglit valve turuiil Uuk at 

 alK>nt an angle of l'*^ for the whole contour in some, for others only from 

 the sinal ear to half way round the contour, instead of the tiro nilirs 

 meeting earh othn nrarli/ tint, as in the prarl oyster ; in having none of the 

 spines with which the pcjirl oyster is covered, and distinctly different 

 flanges ; in liaving no algir adhering to it ; in having the umlx)ne8 more 

 anterior or advance<l Ixyond the hinge line ; in jwlhering to w- V -.■ ' •.» 

 be .^iiragossi/m ruf'iiirr, instead of t^i ro<'k and such-like hard 



