FISHERY BULLETIN: VOL. 70, NO. 2 



Baja California and found two digenea {Otodist- 

 omum sp.) and one cestode from the intestine, 

 one hirudinean { Branc hellion &p.) from the skin 

 surface, and three copepods {Chondracanthus 

 epacthes) and one monogenea from the gills. 

 A monogenea reported from the gills of ratfish 

 from Washington waters was Octobathrium 

 leptogaster (Bonham, 1950). Wilson (1935) 

 reported the copepods Acanthochondria clavata 

 and A. epachthes from the claspers and gills, re- 

 spectively, of H. colliei from California waters. 

 Kabata (1968) could not accept Wilson's (1935) 

 identification of A. clavata, because the species 

 had never been found outside the North Sea, 

 and described A. holocephularum from the clasp- 

 ers of ratfish captured off British Columbia. 



Most morphometric studies of ratfish have 

 been descriptive or histological in nature. San- 

 ford, Clegg, and Bonham (1945) studied the liv- 

 er oil and vitamin A content of 35 ratfish cap- 

 tured off Tatoosh Island, Wash. These factors 

 were related later to size and sex of ratfish by 

 Pidlaoan (1950). Halstead and Bunker (1952) 

 described the venom apparatus and anatomy of 

 the dorsal spine of ratfish. They concluded that 

 the venom of H. colliei was not capable of in- 

 flicting fatal injuries to man. A histological 

 study of the digestive tract and of the pituitary 

 of H. colliei was conducted by Clothier (1957) 

 and Sathyanesan (1965), respectively. 



Stanley (1961) performed a morphometric 

 study of the genital systems of H. colliei and 

 found that summer was the peak reproductive 

 period although one-third of the females and all 

 of the males evidenced reproductive activity 

 throughout the year. Sexual maturity was at- 

 tained at 24-25 cm (S-V)' for females and 18.5- 

 20 cm (S-V) for males. 



METHODS 



Four collections totaling 292 ratfish were made 

 by otter trawl off the coast of Oregon at depths 

 ranging from 50 to 120 fm from 1965 to 1967. 

 The collection from off Newport (iV = 189) was 



frozen while specimens collected off Cape Blanco 

 {N = 44), Cape Arago {N = 35), and Astoria 

 {N = 24) were preserved in 10% Formalin. 



All ratfish were examined as follows: Sex 

 was determined by inspection of the gonads; 

 snout to vent length was measured in milli- 

 meters, and total weight was measured in grams; 

 all specimens were examined for internal and ex- 

 ternal parasites; alimentary canals were exam- 

 ined along their entire length for food items; 

 and dental plates, dorsal spines, left pectoral fins, 

 and a piece of the vertebral column were decal- 

 cified, sectioned frozen, treated with Delafield's 

 hematoxylin stain, and examined for growth 

 structures indicative of age. Both eye lenses 

 were removed from specimens in the Newport 

 and Astoria collections. The wet and dry weight 

 of each lens was determined to the nearest ten 

 thousandth of a gram. For wet-weight deter- 

 minations, lenses were stored in 10% Formalin 

 for 1 month, removed and blotted, and immedi- 

 ately weighed. For dry weight determinations, 

 the lenses were then desiccated at 80°C for 82 hr 

 and reweighed. The 82-hr drying period was 

 determined from a curve of weights of 10 lenses 

 dried at 80 °C and weighed at progressive time 

 intervals. The 82-hr period assured evapora- 

 tion to a stable weight. 



Most statistical analyses of body length-body 

 weight and body length-eye-lens weight relation- 

 ships were performed on a CDC 3300 computer" 

 utilizing program FISH 6669 in the Department 

 at Oregon State University. 



RESULTS AND DISCUSSION 



There was a highly significant correlation 

 (P = 0.01) of body length to body weight for 

 male and female ratfish in the large Newport 

 collection and for the aggregate of each sex col- 

 lected (Table 1). Based on the coefficient of 

 determination (r^) (Croxton, 1953), more than 

 87% of the variation in weight in males and 

 more than 96% in females was attributable to 

 the variation in length of the ratfish. The length- 



* Body length measured from the tip of the snout to 

 the anterior edge of the vent. 



° Reference to trade names in this publication does 

 not imply endorsement of commercial products by the 

 National Marine Fisheries Service. 



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