142 THE ZOOLOGIST. 



GoBIID^l. 

 In this family the sacculus is placed in a recess away to the 

 outer side of the skull and rather high up. The sagitta is large 

 considering the usually small size of the fish. In Gobius jozo 

 and Periopthalmus koelreuteri the sagitta can be seen, the bone 

 being thin. 



Scorp-enid^. 



Sebastes imperialis, a Mediterranean fish, has a skull that, in 

 the part underlying the sagittae, is transparent, and the stones 

 are visible as they lie in the head. The sagitta is embedded in 

 bone all round but open at the top ; the bone has to be cut 

 away to free the sacculus and its contents. The otoliths of 

 S. norvegicus (the Bergylt) (Couch) are fairly large.* 



COTTIDiE. 



The site of the sacculi in " Coitus bulbalis" (the "Bullhead," 

 in Cornwall it is called " Stingdom ") is shown by two small 

 swellings of thin bone. 



Triglid^;. 



In Trigla lyra (the "Piper ") the sacculus lies in a recess so 

 open at the top that the sacculus can be lifted out. It is the 

 same with T. gurnardus (the Gurnard) ; there is no external 

 evidence of the actual location of the otoliths. 



Dactylopterid^e. 

 The sacculus in Dactylopterus volitans (the " Flying Gur- 

 nard ") lies openly on the base of the skull, there being no special 

 cavity for it. 



TRACHINID.E. 



Trachinus vipera (the " Lesser Weever ") shows the position 

 of the sacculus exteriorly by two bulbous excrescences of the 

 basi-occiput, which diverge very much at the anterior ends. The 

 sagitta is confined at both ends, although the pocket is open at 

 the top. The stone is of moderate size. 



NOTOTHENIID2E. 



In Trematomus hansoni, a fish brought from the waters of 

 Victoria Land in the Antarctic, two prominent excrescences of 



* See 'Zoologist,' 1910, p. 293, pi. i., 10. 



