292 



CARL BOVALLIUS, AMPHIPODA inTEEIIDEA. I. 2. 



HY1'EHIID^. 



Euthemisto libelluln. 



The second pair of antennen (Pl. XIII, fig. 5) are longer than the first pair; the 

 third peduncular joiiit is fully as long as the two preceding together. The single fiagellar 

 joint is straight, slender, aiul tapers feebly towards the apex; it is twice as long as the 

 whole peduncle, and is fringed with shoi-t hairs on the under margin. In the young fe- 

 uiale the fiagellar joint is scarcely longer than the peduncle. 



The mouth-or(/a7is are exactly like those in tJie inale. 



The dorsal line of the peroion is very convex; the hfth segment is the longest. 



The epimeral of the fifth pair of perneopoda is the longest, while the preceding de- 

 crease anteriorly in length and the following posteriorly. 



The branchial säcks (Pl. XIII fig. 22) are about half as long as the femora of the 

 corresponding pairs of perasopoda, and ai'e broad, almost truncated at the apex. 



The ovitectrices (PL XIII fig. 22) are elongate-ovate, narrow at the apex, and are 

 considerably longer than the branchial säcks. 



The jjerceopoda (p. 291, fig. 2 and 3) are closely similar to those in the male; in the 

 youiig female the carpal process of the second pair does not reach to the apex of the metacar- 

 pus, but is still much more than half as long as the hind margin of the metacarpus; also the 

 tibial process in this pair, and in the fifth paii", is less produced than in the adult animal, 

 though more produced than, for instance, in the adult animal of Euthemisto compressa. 

 Sometimes the dactylns, and even the metacarpus, of the sixth and seventh pairs is trans- 

 formed for giving outlet to the glandular secretion. 



The pleon is not fully as long as the last five perasonal segments togetlier, and is 

 disfiiictly carinated; the hind cornej" of the segments is sharp-pointed, but not produced. 



The urus is a little longer than the last pleonal segment in the adult female, in 

 the young it is somewhat shorter. 



The uropoda (p. 291, fig. 4) are like those in the male. 



Euthemisto libellula, Mandt. Young female. 

 Copy from C. Bovällius, Aret. and Antarct. Hyper., pl. 47, fig. 104, 107, and 108. 



1. Tlie animal from the side. 2. The first pair of percBopoda. 3. The second pair. 



