56 



Part III. — Twenty -fourth Annual Report 



The earstones of seven fishes of different sizes are represented on 

 Plate i. b. The largest fish was about 15 inches in length and the 

 smallest 7 inches, but though the earstones differ considerably in size 

 they retain to a large extent their characteristic form and sculpture. 

 Their general outline may be thus briefly described. The upper and 

 lower margins are arcuate, but the one rather more so than the other. 

 One end is obliquely truncated, while the other is bifid or forked, and a 

 distinct groove extends from the apex of the fork to almost the opposite 

 end of the earstone. The earstones from the largest fish (15 inches long) 

 measured 4'8mm. in length by about 4mm. in depth, and are thus com- 

 paratively small in proportion to the size of the fish, being only equal to 

 an eightieth part of its length. They are represented by fig. 46. The 

 other fishes in the series measure about 13| inches, 13^ inches, 12| 

 inches, 9 J inches, 7| inches, and 7 inches in length, and the length of 

 their earstones stated in the same order is nearly 4'5mra., 4*0inm., 4 , 3mm., 

 3'Omm., 2'7mm., and 2 , 5mm., their greatest width being about one-fifth 

 less than the length. They were all nearly flat or only slightly incurved. 

 Figs. 12 and 13, pi. iv., represent figs. 50 and 51, on pi. i., b., considerably 

 enlarged. 



Trigla pint, Bloch. The Red Gurnard. PI. i. b., fig. 53; pi. iv., fig. 15. 



The earstones represented by fig. 53 are from a red gurnard 345mm. 

 (nearly 13| inches) in length. They have a general resemblance to those 

 of the grey gurnard, except that the lower margin is produced posteriorly 

 into a sharp point. The extreme length of the earstones is about 5*5mm. 

 by 3*5 in depth. Fig. 15, pi. iv., shows the earstones considerably 

 enlarged. 



Trigla lineata, Gmel. The Streaked Gurnard. PI. i. b., figs. 54 and 55 ; 

 ' pi. iv., fig. 20. 



The two specimens of Trigla lineata whose earstones are represented 

 here measured respectively 10J inches and 8 inches in length. The 

 otoliths, which do not differ much in size, being about 4mm. long by fully 

 2*5mm. in depth, are in their form and markings somewhat similar to 

 those of Trigla gumardus. Fig, 20, pi. iv., shows the earstones, 

 represented by fig. 54, greatly enlarged. 



Trigla lucerna, Linn. The Sapphirine Gurnard. PI. i. b., fig. 56 ; pi. iv., 

 fig. 21 



The earstones of these species have also a general likeness to those of 

 Trigla gumardus. The specimen from which those represented here was 

 obtained measured 10| inches long, and the earstones were about 3-8mm. 

 by 2"5mm. 



Fam. Cataphractid^:. 

 Genus Agonus. 



Agonus cataphractus, Linn. The Pogge. PI. ii. B., fig. 18 ; pi. iii. b., 

 figs. 44-46 ; pi. v., fig. 27. 



Four examples of Agonus ranging from about 6 inches to 4| inches in 

 length were examined for their earstones. These were found to have a 

 narrow oval form, rather obtuse at the one end and pointed at the other 



