136 THE ZOOLOGIST. 



GadidjE. 

 In this family of the Cod and its congeners the sagittal are 

 large, and their location is shown from the outside by a swelling 

 of the basi-occiput, and in some cases, as in Gadus merlangus 

 (the Whiting) and G. minutus (the "Power"), by the thin 

 bone covering the stones allowing the opaque white bodies to be 

 seen. In some the sagitta can be easily picked up from the 

 inside with forceps ; this is the case with Merluaias vulgaris (the 

 Hake) ; in others, a very little clearing away of bone enables 

 the sagitta to be got out. This is so with G. merlangus and with 

 Molva elongata, a Mediterranean relative of the "Ling." In 

 Uraleptus maraldi, another Mediterranean fish, on the contrary, 

 the sacculus is completely embedded in bone, its place shown 

 exteriorly by a large swelling of the basi-occiput, which is out of 

 proportion to the size of the sagitta when this is got out. 



Bekycid.e. 

 Beryx splendens shows its sagittse through the thin bone that 

 underlies them below the skull. These otoliths are large.* 



Pempherid.^. 

 The sagitta in Pempheris russellii is comparatively large. 



Centrarchid-e. 

 In Kuhlia marginata, a fish from New Guinea, the site of the 

 sacculus is marked by a piece of thin bone, slightly elevated, 

 that shows the whole length of the sagitta through it on each 

 side, looking like grains of barley in shape. The sacculus is 

 embedded in a bony pocket requiring to be cut away. The 

 sagitta is a moderate size ; the asteriscus is, however, very small 

 in size, even for this usually small stone. 



Lobotid.e. 

 In Lobotes colonorum the sacculus lies in a strong bony 

 pocket requiring to be much cut away to free it. 



PERCIDiE. 



In Acerina cernua (the Ruff, Pope, or Jack Ruff) the two 

 well-defined pockets holding the sagittae are covered with thin 



* See illustration, 'Zoologist,' 1910, p. 293, pi. i., 9. 



