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Occurrence. — Six females and two males were obtained from the plankton collected 

 at the following stations. 



Stat. 16, one female and one male. — Stat. 118 (HENSEN vertical net, 900 metres to surface), 

 one female. ■ — Stat. 185 (HENSEN vertical net, 1536 metres to surface), two females. — 

 Stat. 213, two females and one male. 



This species is so named in compliment to Sir John Murray, K.C.B., the well known 

 hydrographer, one of the pioneers of oceanic research, whose name is inseparably connected 

 with the Scientific Results of the Exploring Voyage of H. M. S. 'Challenger', 1873 — 1876. 



4. Tortanus brevipes nov. sp. Plate LVI, figs. 9 — 1 



ó- 



Female — length 2,3 mm. 



Viewed from above, the body appears elongate ovate, and moderately robust. The 

 length is distinctly less than three times the width. The head is separated from the first 

 thoracic segment. The fourth and fifth thoracic segments are completely fused together. The 

 last thoracic segment is quite asymmetrical. The right side is produced posteriorly into a wing- 

 like process that reaches to the middle of the genital segment. The left side is also produced, 

 but the prolongation is much shorter, and it is directed at almost right angles to the body 

 (Plate LVI, fig. 9). The eye is large and conspicuous. A small triangular spine is visible under 

 each eye when the Copepod is viewed from the side. 



The abdomen is composed of two segments. The combined length of the abdomen and 

 furca is contained three times in the total length of the ceplialothorax, from the frontal margin 

 to the base of the genital segment. The genital segment is asymmetrical. lts length exceeds 

 the combined length of the anal segment and furcal joints. The anal segment is not separated 

 from the furcal joints. It is comparatively short. The furcal joints are slender and of moderate 

 length. The joints are twice the length of the anal segment and are asymmetrical. The right 

 furcal joint is distinctly shorter and more slender than the left furcal joint. The second inner 

 seta on each furcal joint is long and stout. The furcal joints are furnished with one outer 

 marginal seta (Plate LVI, fig. 9). 



The antennules are composed of sixteen joints and extend slightly beyond the end of 

 the furcal joints. 



The antennae, mandibles, maxillae, maxillipedes and first four pairs of feet are similar 

 to those of Tortanus ^racilis. 



The fifth pair is very small. Each foot is composed of a single free joint attached 

 to a basal part. The free joints are short and broad and slightly asymmetrical (Plate 

 LVI, fig. 13). 



Male unknown. 



This species is rather different from the typical members of the genus. It is easily 

 cognised by the asymmetrical last thoracic segment, and by the abnormal structure of the fifth 

 pair of feet. The apparent abnormality does not arise from any accident to the preparation. 

 The peculiar structure of the fifth pair was quite obvious before the dissection was made. 



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