68 



Part III. — Twenty-fourth Annual Report 



entire length of the fish. The annexed table contains the measurements 

 of a few of the other fishes examined and of the sizes of their otoliths. 



Figure on the 

 plate, (i. b. ) 



Length of the fish. 



Earstones. 



Length. 



Depth. 



14 

 15 

 16 

 17 



220mm. 

 185mm. 

 177 mm. 

 165mm. 



3'7mm. 

 3-lmm. 

 3-lmm. 

 3'lmm. 



2*0mm. 

 17mm. 

 1 "7mm. 

 r7mm. 



The earstones of the three smallest fishes are almost identical in size 

 and shape. 



Genus Raniceps. 



Raniceps raninus (Linn.). The Lesser Fork-beard. PI. i. b., figs. 1-8 ; 

 pi. iv., fig. 6. 



The earstones of the lesser fork-beard or tadpole fish are tolerably large; 

 their outline forms a nearly regular oval ; both the lower and upper mar- 

 gins are moderately thin and convex, and converge towards both ends 

 wbich are narrow and rounded, but the posterior extremity is more pointed 

 than the other. A thickened but obscurely defined rib extends along the 

 middle line from end to end, and gives a massive appearance to the 

 otolith. The largest fish represented here was 12 inches long, and its ear- 

 stones measured — one, fully 14mm., the other 15mm. in length and about 

 7mm. in greatest width, so that in this example the length of the 

 earstones is equal to about the one twenty- second part of the entire length 

 of the fish. 



Fig. 5 represents the earstones of a fish about 8| inches long, and as 

 they measure about 11mm. in length they show almost the same propor- 

 tion to the length of the fish as the other — viz., about one-twentieth part. 

 Fig. 7 represents the earstones of another fish that measured about 

 180mm., and as the earstones are nearly 10mm. in length, it seems to bear 

 out what has been already stated, that in some species and within certain 

 limits the smaller fishes possess earstones relatively larger in proportion 

 to the length of the fish than the adult specimens. The annexed Table 

 gives the length of a number of the fishes examined, with the sizes of 

 their otoliths : — 



Figure on the 



Length of the 



Earstones. 



Plate, (i. b.) 



Fish. 



Length. 



Depth. 



1 



2 



3 

 4 

 5 

 6 

 7 

 8 



12 inches, 



10i „ ...{ 



9| „ 

 9£ „ 

 8| „ 

 7| „ 



n ,, 



4 



1 fully 14 and 1 \ 

 nearly 15mm. j 

 Average of the \ 

 two, 12 - 5mm. J 

 12 -3mm. 

 12 '0mm. 

 11 '2mm. 

 10*7mm. 



9*8mm. 



2*4mm. 



7'Omm. 



6 -Omni. 



5*5mm. 

 5 "3mm. 

 4 '5mm. 

 4"5mm. 

 4 - 5mm. 

 1 'Oram. 



