1004 THE VOYAGE OF H.M.S. CHALLENGER 



the rami long, reaching beyond those of the other pairs, broadly lanceolate, the outer 

 edges nearly straight, except at the distal end, the inner edges deeply serrate as well as 

 pectinate, narrowing rapidly at the distal end to the acute apex, which on the outer ramus 

 forms a small nail, and by so much extends beyond the inner ramus. Each ramus shows 

 the remains of a fringe of setae on the inner edge, the setae being densely plumose and 

 some of them of great length ; the outer ramus has one or two spines in notches on its 

 outer margin above the apex. 



The Telson reaches considerably beyond the peduncles of the third uropods ; the 

 length about once and a half the breadth, cleft almost to the base, each division sharply 

 incised at the apex, the outer point being produced beyond the inner, both acute, the 

 interval between the outer apical points being rather less than half the breadth near the 

 base. 



Length. — The length of the specimen was unfortunately not taken before dis- 

 section ; it was, I believe, without the antennae, about two-fifths of an inch. 



Locality. — Station 295, off the west coast of South America, November, 5, 1875 ; 

 lat. 38° T S., long. 94° 4' W.; depth, 1500 fathoms; bottom, Globigerina ooze; 

 bottom temperature, 35°"3. One specimen, female. In the tow-net attached to the 

 trawl. 



Remarks. — The specimen had been mounted in glycerine during the voyage, and was 

 labelled "Tow-net at the trawl, 6 Nov. 1875, 1500 fathoms." There can be no doubt 

 this refers to Station 295. 



The specific name, from the Greek /Aa/cpos, long, and 6vv%, nail, alludes to the fact that 

 the fingers (ungues of Latin descriptions) are long in both the gnathopods and (so far as 

 observed) in all the peraeopods in this species. 



Family Gammarid^e, Leach, 1814. 



In 1870 Boeck adopted the title " Garuniarinas. Dana, 1849," for the fifteenth sub- 

 family of the family Gammaridae. In it he included the genera, Gammarus, Pallasia, 

 Msera, Melita, Elasmopus, Cheiroeratus, Gammar acanthus, Nip)hargus, Amathilla, 

 Melphidipjpa. In 1872-1876 he made the Gammarinae the eighth subfamily of the 

 Gammaridae, with the same definition and including the same genera as before. In 

 1882 Sars changed the subfamily into a family, with the title Gammaridae, presumably 

 accepting Boeck's definition, as he includes in it the same list of genera without addition 

 or diminution, and with only the nominal exchange of Eriopis, Bruzelius, for Niphargus, 

 Schiodte. For this group Boeck gives the following definition : — 



" Mandibles both alike, robust, apically dentate ; the inner plate also dentate ; the 

 molar tubercle very prominent ; the palp elongate, three -jointed. 



