. 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 th
. 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
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