occurring on the Norwegian Coasts. 403 



typical species, 8. validus and 8. polyprton, Costa, a new 

 Norwegian species which I have called 



8. Danai, mihi. — I found a female of this species at Farsund, 

 at a depth of 15 fathoms. It is not quite 5 millims. in length, 

 and differs from the two other species in the form of the first 

 two pairs of hands, of the fourth epimera, and of the abdomen. 

 The third joint of the first pair of legs has its inferior posterior 

 angle much elongated into a thick process, which is as long as 

 the folloAving joint. The hands are shorter than the preceding- 

 joint ; the fifth joint or hand of the second pair of feet is ex- 

 tremely large and oval, and its posterior margin furnished 

 with many blunt teeth and with two long spines, which reach 

 the apex of the finger. The fourth epimera are much longer 

 than broad, and become narrower behind, but not emarginate 

 for the fifth, as in 8. validus. The outer branch of the fifth 

 pair of abdominal legs is much shorter than the inner one, 

 and the peduncle of the last pair of abdominal feet is much 

 longer than in 8. validus. 



Eusirus, Kr. — Dana thought that this genus of Kroyer's 

 differed so little from Gammarus, that it must be merged in 

 it. Bruzelius certainly accepted it as a genus, but thought 

 that it stood very near to Gammarus. I think, however, that 

 these genera have few characters in common, except the se- 

 condary flagellum, and this is very small. At the first glance 

 there appears to be a great agreement between this genus and 

 Leucothoe. In both the third joint of the peduncle of the su- 

 perior antennas is small, and the first two pairs of hands are 

 nearly of the same form. Both have the following pair of 

 legs long, slender, and feeble, whilst in Gammarus they are 

 strong ; and, finally, the very long abdominal feet and telson, 

 as also the large first epimera, are very characteristic external 

 peculiarities of the two genera. Similar agreements occur in 

 the more concealed parts. The mandibles certainly differ, in- 

 asmuch as in Eusirus they possess a masticatory tubercle ; 

 but the first pair of maxillary palpi have the same form in 

 both, and are divided into two nearly equal large joints. The 

 inner lamella is furnished only with a single hair, contrary to 

 what occurs in Gammarus. The masticatory lamella? of the 

 maxillipedes are small, and the palpi much elongated, but 

 rather strong. To this genus a new species may be added, 

 belonging to our fauna : — 



E. longipes, mihi. — The third joint of the superior antennas 

 is longer than in E. cuspidatus ; and the flagellum consists in 

 the males of fifty-four joints furnished with sucking-disks, 

 and in the females of forty-two. The fifth joint of the in- 

 ferior antennae is shorter than the fourth ; in the females it is 



31* 



