I 20 



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 Tcmoropia 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 lenoth. 



12. Family Metridiidae. 

 Genus Metridia Boeck, 1864. 



The members of this genus are separated from Plcnromamma, 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 boecki Giesbrecht. Plate XXXVII, figs. 12 — 14. 



Metridia boecki Giesbrecht, 1889, p. 24. 



Metridia boecki Giesbrecht, 1S93, p. 340, pi. 33. 



Metridia boecki Giesbrecht & Schmeil, 1898, p. 107. 



Metridia boecki Esterly, 1905, p. 178, fig. 354/. 



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 (900 metres to surface). — Stat. 141 (1500 metres to surface). — Stat. 148, fiooo 

 metres to surface). — Stat. 203 (1500 metres to surface). — Stat. 276 (750 metres to surface). 



The females of Metridia boecki bear a close resemblance to the females of Metridia 

 Ineens, 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 ineens has only two 

 free joints. 



The species, so far, has only been recorded by Giesbrecht in the Fauna und Flora 

 des Golfes von Neapel and by Esterly from the Pacific, off San Diego. 



2. Metridia brevicanda Giesbrecht. Plate XXXVII, figs. 9 — 11. 



Metridia brevicanda Giesbrecht, 1SS9, p. 24. 

 Metridia brevicanda Giesbrecht, 1893, p. 340, pi. 33. 

 Metridia brevicanda Giesbrecht & Schmeil, 1898, p. 108. 

 Metridia brevicanda Wollenden, 1904, p. 111. 

 Metridia brevicanda Cleve, 1904, p. 192. 

 Metridia brevicanda Pearson, 1906, p. 24. 

 Metridia brevicanda Farran, 1908, p. 60. 

 Metridia brevicanda van Breemen, 1908, p. 111, fig. 128. 



120 



