278 THE VOYAGE OF H.M.S. CHALLENGER. 



long, with long lanceolate rami projecting beyond the others. The tail terminates in two 

 long spines. Colour wine-yellow ; inferior antennae annulate with reddish. Length, 

 0'32 inch. Dredged in forty fathoms, on a soft muddy bottom off Long Island, G. M." 

 It is scarcely necessary to remark that the armature of this species must distinguish it in 

 a striking manner from the Lysianassinoe in general. Of his Armnyx nohilis, Stimpson 

 says that it most resembles Anonyx appendieulosus, Kr0yer, but the distinctions he 

 mentions do not suffice to separate the two species, and Anoinjx appencJiculosus itself is not 

 distinct from Anonyx nurjax, Pliipps. Anonyx politus, n. sp., according to Spence Bate, 

 has nothing in the description to distinguish it from Anonyx liolbolli. Anonyx Iwlhulli of 

 Bate, according to Boeck, = Anonyx gulosus, Kr0yer, from which it may be inferred that 

 Anonyx p)olitus is a synonym of Anonyx gulosus, which is itself probably the same as 

 " Oniscus Cicada," Fabricius. The new species Anomjx pallidus and Anonyx exiguus are 

 both endorsed by Spence Bate, as also Stenothoe clypeata and Leucothoe grandimanus, 

 although of the latter he observes, "this species closely resembles Leucothoe ai'ticulosa. 

 The only differences seem to be the small coxas, the length of the dactylos of the first 

 pair of gnathopoda, and the colour of the American species." It may be noted that the 

 dactylos of the first pair of gnathopoda in Stimpson's drawing agrees with that of Leiicotlwe 

 {articidosa) spiniearim, so that the species must be considered doubtful. 



Oniscus serratus of Otho Fabricius is here named Acanthonotus seiraius, a name which Eoeck 

 alters into Acanthonoiozoma serratum. Amp)Mtlionotus caiaphractus, n. sp., is regarded by 

 Boeck as a type for the genus which ho calls Tritrojns, a i^reoccupied name, altered by 

 S. I. Smith to Rhachotropis. Ampihitlwnotus, Costa, had lapsed as a synonym of 

 Dexamine. 



Ampliitlwe virescens is identified by Spence Bate with Amp)lnthoe jmnctata, Say. Amphithoi: 

 maculata, Stimpson says, " differs from the last species in being more robust and of 

 a much harder structure; also totally in coloration." As the Amphipoda are sometimes 

 extremely soft just after shedding the skin, one is inclined to believe that Stimpson may 

 have laid too much weight on the texture of the integument, in separating this species 

 from the preceding one. Iphimedia vulgaris, which is said to differ from Amphithoe 

 inermis, KrOyer, by "its larger eyes and epimera, and much longer caudal stylets," is 

 renamed by Sp. Bate Afyhis vidgaris. Ampliitlwe inermis is taken by Axel Eoeck as 

 type of his genus Pontogeneia. 



The new genus Monoculodes is thus defined: — "Body tumid anteriorly; head rostrate, with 

 the eyes so close together as to appear one. Superior antennfe without accessory flagellum ; 

 inferior ones subpediform. Legs of the first two pairs with large subcheliform hands, 

 formed of the last two articles of each ; the antepenult joints having their inferior apices 

 produced into slender thumbs. Legs of the posterior five pairs unguiculate, those of the 

 last pair being exceedingly long. Caudal stylets all biramous ; the rami being equal. 

 Maxillipeds Large, elongated, with unguiform terminal articles, and internal lamellae of 

 about one-half their length. Mandibles palpigerous." Stimpson adds, " this genus 

 resembles Eusiriis in the structure of the hands, and CEdicerus in its long posterior feet." 

 The type species is Monocidodes demissus. The next two species mentioned are 

 Gammarus sahinii, Leach, and Gammarus macropthalmus, n. sp., the latter of which is 

 named by Spence Bate Gammaracantlms macropldliahnus. Gammarus pidex, which 

 Stimpson names as equivalent to Cancer pulex, Lin., Oniscus p>ulex, Mull., 0. Fabr., 

 and Gammariis locusta of Montagu, Kr0yer and Gould, is referred by Spence Bate, 

 who had received specimens from Stimpson, to Gammarus ornntus, Milne-Edwards, 

 and later on by Stimpson himself to Gammarus locusta, J. C, Fabr. Gammarus 

 purpuratus, identified both by Bate and Boeck with Gammarus dentatus, Kr0yer, is 

 placed by Bate in his genus Megammra, by Boeck in the genus Melita, Leach. 



