lipeds more robust, with the terminal part reflexed. The 4 anterior pairs of legs 

 comparatively short and compact, with both mini triarticulate and less unequal 

 than in the Hetcntrhilxlnltv. Last pair of legs not natatory in either* of the sexes, 

 inner ramus rudimentary or quite wanting. 



ttcmarte. The type of this new family is the genus Ar'n't<Uu* of Gies- 

 brecht, which was referred by that author to his subfamily Hctcrorha-fimr. 

 though in some respects, and more especially in the structure of the last pair of 

 legs, it differs very materially from the 3 genera now included in the family 

 On the other hand, it exhibits a close relationship to the genus 

 of Scott, as also to another new genus, Scott nla. to be described 

 below, these 3 genera accordingly forming together a natural group or family. 

 The chief distinctive character of this family, as compared witli the Hctcrorhnhiliilii', 

 is the very different structure of the last pair of legs, these in the latter family being 

 natatory like the preceding ones, whereas in the present family they are much 

 reduced in size, and not at all natatory in either of the sexes. This is appar- 

 ently a character of fundamental importance, and has for this reason been taken 

 into consideration in the distinction of several other Calanoid families. Another 

 peculiar feature characteristic of the present family, is the inequality of tlu> 

 anterior antenna) in both sexes, the left one being the longer. This inequality 

 is especially conspicuous in the genus Scottula, and is also present, though in a 

 less conspicuous manner, in the genus Paramisophria. In the typical genus 

 ArictcllHt*, it is true, no mention of such an inequality has been made; but, 

 taking into consideration the near relationship of this genus to Par<nniw>i>hri<t, 

 it seems to me very probable that this character has been overlooked, as it 

 actually was previously in the case Qt Paramisophria. Of the 3 genera at present 

 comprised within the family Arietellida. 1 , 2 are represented in the fauna of Norway, 

 and will be treated of below. 



Gen. 22. SCOttula, G. O. Sars, n. 



/c Clmnictcrn. Body quite calanoid in appearance, with the anterior 

 division moderately tmm'tii'd; front considerably produced below, and carrying "2 

 straight tentacular appendages. Last segment of metasome simple, without any 

 subdorsal projections. Urosome moderately slender, with the genital segment in 

 female comparatively short. Caudal rami with 3 of the setae much elongated, 



