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margin are not grouped, densely packed and of equal size. (7) The 

 fourth pleopod of the male (fig. 78, b) has the proximal joint of the 

 exopod six times as long as the distal joint; terminal setae one-quarter 

 longer than the distal joint. 



This species was described by Czerniavsky (1882b) from specimens 

 taken in the North Pacific in the Gulf of Castries. It was later re- 

 corded by Dershavin (1913), without comment, from Kamchatka and 



Figure 78. — Neomysis mirabilis (Czerniavksy) : a, Antennal scale and peduncle, X 22%; 

 b, fourth pleopod of male, X 26%; c, telson of typical form, X 22%; d, telson of a not 

 uncommon variety, X 30%. 



by Birstein (1939) from Asiatic Russia. Birstein gave a figure of the 

 telson which agrees with that of the present material. Ii (1936a) has 

 described a species, N. nakazawai, which appears to me to be indistin- 

 guishable from N. mirabilis. He makes no reference whatsoever to 

 the latter species, and I can only suppose that he overlooked 

 Czerniavsky's description, not perhaps recognizing that the genus 

 Heteromysis of Czerniavsky, of which this species is the type, is only 



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