occurring on the Norwegian Coasts. 329 



between the upper and lower antenna? is much larger and 

 more strongly prominent. 



Genus 2. Lestrigonus. — This genus is also represented on 

 our coast by two species. The first of these may, I think, be 

 identified with Kroyer's L. exulans, although it differs from 

 this in its considerable size and also in having the upper an- 

 tenna? longer than the head and the first two segments toge- 

 ther, and their flagella composed of seventeen short joints. 

 The first joint of the flagellum is, moreover, shorter than in 

 L. extdaiiSj and of a different form ; but it is possible that 

 Kroyer's specimen was not perfectly developed. These parts 

 vary both in form and size according to age. I have there- 

 fore for the present cited it under the above name. 



The second species, L. Boeckiij resembles the preceding one 

 in size; but the antenna? are very nearly of the same length as 

 the body. The first joint of the peduncle in the upper an- 

 tenna; is very short, and the flagellum is formed of eighteen 

 very long and thin joints. The third and especially the fourth 

 joints of the inferior antenna?, when compared with those of 

 the preceding species, are much longer, and their extreme end 

 is furnished with more teeth ; the fifth joint is about half as 

 long as the fourth. The flagellum is formed of twenty-four 

 long and slender joints. The eyes are very large, and occupy 

 the whole side of the head, becoming contiguous above. The 

 claws of the first two pairs of feet are denticulated on the 

 upper part of the hinder edge. The last three pairs of thoracic 

 legs are not much longer than the preceding. 



The first of these species was found near Beian and Sond- 

 mor by Professors Rasch and Boeck ; the second was found 

 as long ago as 1818, in the Christiania-fjord, by Professor C. 

 Boeck, and also subsequently by him at Beian. 



A remarkable transition between this and the next tribe is 

 constituted by a new form, which differs so much from both, 

 especially with regard to the parts of the mouth, that it cannot 

 find a place in either of these, and therefore must be set up as 

 a separate tribe and family. 



Tribe II. Peostomat.E, mini. — This includes only one 

 genus and species, which M. Esmark, who first distinguished 

 its aberrant form, indicated under the generic name of Tri- 

 schizostoma, naming the species, after its discoverer, T. 

 Saschn. 



This Amphipod, according to Professor Rasch's statement, 

 was taken by him at Havbroen, off the coast of Sondmor, by 

 sinking a dead bird to a depth of about 100 fathoms. To this 

 three specimens, all females, attached themselves. He is not, 



