377 



]iio(lnreil in front to a cnrved acuminate rostrum, lateral corners small, 

 deilexed. Coxal plates nearly as in the preceding genus. Eyes well developed 

 and rather large. Antennse comparatively slender and subequal in length, 

 peduncle of the superior ones rather short. Anterior and posterior lips com- 

 paratively broader than in the preceding genus, the latter having the lobes 

 incised interiorly at a short distance from the tip. Mandibles less elongated, 

 with the cutting edge but very slightly dentated and the secondary lamella 

 larger, molar expansion wanting, palp comparatively strong. Maxillae nearly as 

 in Acanllionotosoma, though somewhat less elongated, and having the basal lobe 

 shorter. Maxillipeds with the basal part rather narrow, masticatory and basal 

 lobes well developed, palp comparatively large and densely setous, with the 

 joints laminarly compressed, the 2nd forming interiorly a rounded expansion, 

 dactylus wholly wanting. Both pairs of gnathopoda extremely slender, the 

 anterior ones terminating in a complete though very small chela, the posterior 

 ones imperfectly chelate, the propodos being produced at the end, below the 

 insertion of the dactylus, to abroad, setous lobe, against which the latter is 

 allowed to impinge. Pereiopoda of normal appearance, basal joint of the '6 

 posterior pairs rather broad, laminar. Last pair of uropoda with the rami 

 narrowly lanceolate. Telson broadly incised at the tip. 



Bcmarks. — The present genus was first established in the year 1843 

 by H. Rathke, to include the species «o6es«», to be described below. With 

 this, the Kroyerian genus MicrocJieks is undoubtedly identical, as also the 

 genus Panoplcea established by Thomson to include a New Zealand species. 

 The genus is chiefly characterised by the peculiar structure of the gnatho- 

 poda, both pairs of which are very slender and more or less distinctly cheli- 

 form. Moreover the acuminate lappets, into which the posterior edge of some 

 of the segments are divided, give the species a rather characteristic appea- 

 rance. Several species of this genus have been described by different authors 

 from different parts of the Oceans, some of which, as I. eblancc Sp. Bate, 

 liave turned out to be truly parasitic in habits. To the Norwegian fauna 

 belong 2 distinct species, to be described in the seqiiel. 



3. Iphimedia obesa, Eathke. 



(PI. 132). 



Ilihimedia ohesa, Kathke, Acta Acad. Leop. T. XX, p. 85, PI., fig. 



Syu.: Microcheles armata, Kroyer. 



Body rather robust of form, and somewhat tumid in its anterior part, witli 



the" posterior edge of the last segment ofmetasome and of those of metasome 



divided dorsally into2 juxtaposed, acuminate lappets. Cephalon rather deep and 



;ibout the length of the first 2 segments of mesosome combined, rostrum strongly 



curved, and reaching somewhat beyond the basal joint of the sixperior antennae, 



