84 THE VOYAGE OF H.M.S. CHALLENGEE. 



since called Anceus, and the last witli tlie genus Apgeudes, are not usually considered 

 Amphipod families. 



In this system we have the following arrangement of the genera and species which came soon 

 after to be called Amphipoda. 



" Family XIV. Gammabini. 



" 1. Superior antennae shorter than the peduncle of the inferior antennae. Feet fourteen." 

 " Genus LIII. Talitrus." " Sp. 1. Locusta." " Cancer loeusta of Pennant and Gmelin. 

 Onigcus loaisfa of Pallas. Gavimarus locusta of Fabricius ? Cancer gammarus saltator 

 of Montagu. Talitrus locusta of Latreille." " Sp. 2. Littoralis." " Talitrus littoralis. 

 Leach's MSS." This was afterwards dropped. "Genus LIV. Oechestia." " Sp. 1. 

 lAttorea." " See Plate ccxxL fig. 6. Ptilex marinus of Baxter [Easier] ; Cancer gammarus 

 littoreus of Montagu ; Orchestes littorea, Leach's MSS.; Talitrus gammarelliis,'L&iT:ei\^Q'i" 

 "Latreille quotes Baxter's figure which renders it highly probable that this may be his 

 Talitrus gammarelliw ; but as he quotes also the Oniscus gammarellus of Pallas, it still 

 remains in some doubt." This confusion on Leach's part probably originates with Montagu. 

 See Note on Montagu, 1808. 



" 2. Superior antennae longer ; or at least as long as the inferior. Fourteen feet, the third and 

 fourth pair smallest." " Genus LV. Gammaehs." "Freshwater. Sp. \. Pulex." "Cancer 

 pulex of Linne and Pennant ; Gammarus pulex of Fabricius and Latreille." " A species 

 which Mr. Leach considers as distinct from pulex " is then mentioned, but not numbered. 

 It came from a well in London. " It differs principally from Gammarus piulex in having 

 the upper process of the tail much longer. The colour, when alive, was cinereous, but so 

 translucent, that the eyes could not be discovered ; it stands in Mr. Leach's cabinet, under 

 the specific name suhterraneus." This is probably the same as Niphargus aquilex, Schi0dte. 

 The species of (?a77!Ma?-«is are continued under the heading "Marine." "/Sp. 2. Locusta." 

 " Cancer locusta of Linn6. Is it Cancer gammarus locusta of Montagu 1 Linn. Trans. 

 Tol. ix." " Sp. 3. Camylops." This is probably only a casual variety of Gammarus 

 locusta. " Sp. 4. Rubricatus." "Cancer gammarus rubricatus of Montagu. Ampithiie 

 rubricata, Leach's MSS." " It is a rare species, and possibly does not belong to this 

 genus." "Genus L'VI. Maera. Anterior pair of feet with a moveable nail ; the second 

 pair with a compressed hand and moveable thumb. Peduncle of the antennae with three 

 joints ; the superior antennas longest." " Sp. 1. Grossimana." " Cancer gammarus 

 grossimanus of Montagu. Miera grossimana, Leach's MSS." " Genus LVII. Melita. 

 Anterior pair of feet very small ; second pair with a compressed hand, and moveable nail 

 which bends on the palm. Superior styles of the tail very long and large." " Sp. 1. 

 Palmata." " Gammarus palmata, Montagu, Linnean Transactions, vol. vii. tab. 6. 

 Melita palmata, Leach's MSS." " Genus LVIII. Leucothoe. Anterior feet with a 

 finger and thumb ; the thumb jointed ; second pair with a moveable thumb but no finger. 

 Peduncle of the antennae with two joints. Superior antennae longest." " Sp. 1. Articulosa." 

 " Cancer articulos^is of Montagu. LeucothiJe articulosa. Leach's MSS." This is now 

 known as Leucothoe spinicarpia (MiiUer) Abildgaard. 



Leach then observes that Phronima sedenfaria of Latreille, " Cancer sedentarius Forsk. F. Arah. 

 page 95," probably forms a distinct family, but as he had never seen a specimen, he merely 

 quotes some remarks of Latreille upon it, and then proceeds to give : — 



"Family XV. Corophini. Genus LIX. CoROPHinn." " Sp. 1. Longicomes." "Cancer 

 grossipes of Linn^ ; Oniscus volutator of Pallas ; Gammarus longicornis of Fabricius ; 

 Astacus linearis of Pennant ; and Corophium longicorne of LatreiUe." 



" Family XVI. Caprellini," with a note : — " The body of these animals, exclusive of the head, 

 is composed of six joints, all except the second and third bearing feet. The second and 

 third segments furnished on each side with two processes, which probably serve as fins. 



