106 



Remarks. — The type of this family is the peculiar genus Munna of Kroyer, 

 with which several other genera may be conveniently associated, to form a rather 

 well-defined group of Ascllota. From the laniridce, these Isopods may be easily 

 distinguished by the comparatively short and stout body, which, unlike the 

 body in that family, is conspicuously narrowed behind, with the 3 posterior 

 segments of the mesosome much smaller than the 4 anterior ones, and the caudal 

 segment ob-pyriform in shape. Besides the 4 Norwegian genera treated of below, 

 the following genera may with certainty be referred to this family: Leptaspidia 

 Bate & Westw., Neasellus Beddard, Astrurus Beddard, Munnella Bonnier, and 

 HaUacris Pfeffer. The last-named genus, however, is, scarcely different, generic- 

 ally, from Munna. 



Gen. 1. Munna, Boeck, 1839. 



? Syn: HaUacris, Pfeffer. 



Generic Characters. — Body sub-pyriform in shape, with the dorsal face some- 

 what vaulted, and the last. 3 segments of mesosome very small, with the lateral 

 parts curving more or less posteriorly. Cephalon very broad, with the frontal 

 margin obtusely produced. Caudal segment narrow, ob-pyriform, and very sharply 

 defined from the mesosome. Eyes distinct, placed on the tips of greatly produced 

 lateral projections of the head. Superior antennae comparatively small; inferior 

 antennae, on the other hand, very much elongated, with the peduncle 5-articulate, 

 the 2 outer joints long and slender. Mandibles with the cutting part divided 

 from the cylindrical molar expansion by a deep incision, palp well developed. 

 1st pair of legs in female comparatively small, imperfectly subcheliform, in male 

 more strongly developed, and sometimes of quite an extraordinary size. The re- 

 maining legs rapidly increasing in length, with the carpal and propodal joints 

 much elongated and edged with spines, dactylar joint small, bi-unguiculate. Middle 

 piece of male operculum rather narrow, sublinear, truncated at the tip. Uropoda 

 very small, simple. 



Remarks. — This genus was established by Kroyer in the year 1S39, to 

 include a peculiar Isopod found by him off the Norwegian coast. Subsequently 

 several additional species were detected by different authors, and the relation of this 

 genus to other Isopoda was more fully recognized. The external appearance is rather 

 peculiar, the apparently stalked eyes especially being very striking. In ovigerous 

 females, moreover, owing to the greatly projecting incubatory pouch, the fore-part of 



