264 



DISCOVERY REPORTS 



Fig. II, and the characteristically shallow depth distribution can be seen in Fig. 18. One specimen 

 was secured with the small beam trawl, all the others with ' Trawl + accessory nets'. It will be seen 

 that the distribution is almost co-extensive with that of another shallow-water species, Psammobatis 

 scobina, but Raja magellanica was found slightly farther south at some points, and tends to occur 



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Fig. II. Distribution oi Raja magellanica. First survey: triangles; second survey: squares; third 

 survey: circles; negative observations left blank. 



With greater relative frequency in the southern region. Thus of the totals of the two species, less than 

 30% of the Psammobatis were from the southern region, but 48% of the Raja magellanica were taken 

 there. Although the observed sex ratio of this species was practically 'normal', there was a hint of 

 segregation mto a unisexual shoal at one station. This is a marked feature in some of the more abun- 

 dant elasmobranchs of British seas and may then lead to a most anomalous apparent sex ratio 

 especially in commercial landings, which may be further distorted by greater value and ease of capture 



