120 
The form recorded by G. P. Farran (1908), from the deep water off the West of Ireland 
as this species, is apparently not identical. Farran states that the fifth pair of feet of the female 
is symmetrical, and his illustration shews that the last joint is furnished with a claw-like spine 
at the apex. In 7emoropra mayumbaensis the last joint of the female fifth pair is asymmetrical 
and the apex is dentate. The ‘Siboga’ specimens are identical with the illustrations given in 
the report ‘On Entomostraca from the Gulf of Guinea’. FARRAN’s specimens measured 7,2—8 mm. 
in length. 
12. Family MErRipqipAer. 
Genus Metridia Boeck, 1864. 
The members of this genus are separated from Pleuromamma, chiefly by the absence 
of a pigmented luminous organ on the side of the first thoracic segment. 
Five species were represented in the plankton collected by the ‘Siboga’ in the Malay 
Archipelago. 
1. Metridia boecke Giesbrecht. Plate XXXVII, figs. 12—14. 
Metridia boecki Giesbrecht, 1889, p. 24. 
Metridia boecki Giesbrecht, 1893, p. 340, pl. 33. 
Metridia boecki Giesbrecht & Schmeil, 1898, p. 107. 
Metridia boeckt Esterly, 1905, p. 178, fig. 35d. 
One female belonging to this species, was obtained from the plankton collected with 
the HenseN vertical net at each of the following five stations. 
Stat. 118 (g0o metres to surface). — Stat. 141 (1500 metres to surface). — Stat. 148, (1000 
metres to surface). — Stat. 203 (1500 metres to surface). — Stat. 276 (750 metres to surface). 
The females of JZetridia boeckt bear a close resemblance to the females of MWetrzdia 
Zucens, but the furcal joints are as long as the anal segment, and the fifth pair is composed 
of three free joints attached to a basal part. The fifth pair of Metridia lucens has only two 
free joints. 
The species, so far, has only been recorded by Guessprecur in the Fauna und Flora 
des Golfes von Neapel and by Esterty from the Pacific, off San Diego. 
2. Metridia brevicauda Giesbrecht. Plate XXXVII, figs. g—11. 
Metridia brevicauda Giesbrecht, 1889, p. 24. 
Metridia brevicauda Giesbrecht, 1893, p. 340, pl. 33. 
Metridia brevicauda Giesbrecht & Schmeil, 1898, p. 108. 
Metridia brevicauda Wolfenden, 1904, p. 111. 
Metridia brevicauda Cleve, 1904, p. 192. 
Metridia brevicauda Pearson, 1906, p. 24. 
Metridia brevicauda Farran, 1908, p. 60. 
Metridia brevicauda van Breemer, 1908, p. 111, fig. 128. 
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