43 



generally double. Anterior antennse in female of moderate length or compara- 

 tively short, 23- or 24-articulate ; those of male with the usual supply of sensory 

 appendages, and having some of the articulations confluent. Posterior antennse 

 with the outer ram us generally longer than the inner, and 6-articulate. Oral parts 

 on the whole normal, except the anterior maxillipeds, which are rather short and 

 clearly characterised by the peculiar transformation of the setae of the terminal 

 part into extremely delicate, incurved cylindric appendages terminating in a brush 

 of fine cilia?. ' Natatory legs strongly built, and of a structure similar to that in 

 the ^Etideidce. 5th pair of legs in female generally present, though rather small, 

 triarticulate, not natatory ; those in male comparatively simple, left leg the longer. 

 Remarks. This new family is established to comprise some genera referred 

 by Dr. Giesbrecht to his subfamily Scolecithritince, for which the genus Scolecithrix 

 of Brady is the type. As, however, the species referred to the latter genus in 

 reality belong to several distinct genera, I have felt justified in comprising those 

 genera in a separate family, Scolecithricidce, to be treated of farther on. The chief 

 character of the present family consists in the peculiar transformation of the setse 

 of the terminal part of the anterior maxillipeds to extremely delicate penicillate 

 appendages, not found in any of the preceding families. In other respects, the forms 

 belonging to this family recall, both in their external appearance and in several of 

 the structural details, that of the ^Etideidoe. Whereas, however, in the latter family 

 the 5th pair of legs are always wanting in the female, these legs are generally 

 present, though in a rudimentary state, in the Phaennidce. We know at present 

 of 3 distinct genera belonging to this family, viz., Phaenna, Claus, Pseudopliaenna, 

 G. 0. Sars, and Xanihocalanits, Giesbrecht. Of these the 2 last-mentioned are 

 represented in the fauna of Norway. 



Gen. 11. PseudOphaenna, G. 0. Sars, n. 



Generic Characters. Body comparatively short and stout, with the anterior 

 division considerably tumefied. Cephalosome completely coalesced with the 1st 

 pedigerous segment, frontal part rounded and projecting below in an undivided 

 rostrum, obtuse at the tip. Last segment of metasome very small, but distinctly 

 defined from the preceding one, lateral lobes but slightly produced. Urosome in 

 female comparatively short, 4-articulate, in male more slender, last segment in 

 both sexes rather small. Caudal rami short, obtusely rounded at the tip, apical 

 setse rather elongated, appendicular bristle small. Eye consisting of two closely 



