FISHERY BULLETIN: VOL. 87. NO. 4, 1989 



lengthy periods (more than 6 months), 70% iso- 

 propanol became weakly acidic with a pH of 6.5- 

 6.7. All otic complexes were removed from heads 

 within three weeks of initial fixation. Samples 

 were then photographed with a Wild M400' 

 photomicroscope before their otoliths were re- 

 moved in preparation for scanning electron 

 microscopy (SEM). Selected whole and fractured 

 portions were then dehydrated in an ethanol 

 series, mounted on stubs with a metallic cement, 

 and sputter-coated with gold under five atmos- 

 pheres of pressure before being viewed on a 

 Philips 505 SEM. 



Analyses of samples by x-ray diffraction were 

 carried out on a Philips PW1279/PW1710 x-ray 

 diffractometer. Operating conditions for the dif- 

 fractometer were the following: 45 kV for the Cu 

 tube; 40 mA for the automatic divergence slit; 

 0.1 mm for the receiving slit; 1° for the scatter 

 slit; and a Ni filter. Goniometer speed was set at 

 3°29/min, and chart speed was set at 10 min/°26 

 from 5 to 55°2e. The error of estimated propor- 

 tion of calcium carbonate morph (calcite, ara- 

 gonite, and vaterite) was ±5%. Otoconial di- 



'Reference to trade names does not imply endorsement by 

 the National Marine Fisheries Service, NOAA. 



ameters were directly measured from SEM 

 photographs. 



RESULTS 



The general shape and organization of the four 

 chimaeriform otic complexes (including semi- 

 circular canals and otoliths) resembled the shape 

 and organization of C. milii (Gauldie et al. 1987). 

 Two otoliths occurred within a single sac, 

 oriented at more or less right angles to each 

 other, and presumably corresponded with the 

 sagitta and astericus of teleosts. All of the oto- 

 liths described in this study were the sagittae. 



The otoliths of the Chimaeriformes were solid 

 masses of aggregated otoconia (Fig. lA, B, C). 

 Otoliths of H. novaezelandiae had densely 

 packed central areas with looser aggi'egations of 

 otoconia on the exterior surface (Fig. IB). The 

 matrix was less apparent in H. raleighana, and 

 the otolith was characterized by many small 

 otoconia (Fig. IC), giving a loose gi'anular ap- 

 pearance, while Rhinochimaera sp. otoliths 

 (Fig. 2A) had closely packed arrays of otoconia. 

 Chimaera sp. otoliths (Fig. 2B) were soHdly 

 packed with less cohesive matrix material 

 visible. 



Ps»' 









h'lGiiKt; lA. — RhmochiDiaem sp. otolith. Bar = 1 mm. 



924 



