REPORT ON THE AMPHIPODA. 267 



tongensif, pcregrina, hreeijies, hrasiliensis, Jilicornis, names hitherto unimpeached, except 

 that, in regard to hrasiiiensig, the B. M. C. observes that " the description of this species 

 closely resembles that of A. GaiuUchawlii of Edwards, the chief distinction being the 

 length of the flagellum of the inferior antennas," but a more important distinction is that 

 in Milne-J]dwards' species the first joint of the first and second perseopods is " ovalaire (au 

 lieu d'etre presque lineaire comme d'ordinaire);" of the species assigned by Dana to Gammarus, 

 Spenoe Bate leaves only one in that genus ; Gammarug asper is called in the B. M. C. 

 Megammra asjKva ; Gammarus sitlueiifiig, as to which Dana says " [Anfemina G. asperi 1]," 

 is called in the B. M. C. " Mer/Miioira Suluemi»," but seeing that the mandibular palp 

 has the second joint much shorter than the first, it probably belongs to a distinct genus, 

 perhaps including Gammarus asper, since Dana says of these two, "they are alike in the 

 very slender mandibular palpi without a ciliated arrangement of hairs on the apical joint " ; 

 Gammarus alhidus in the B. M. C. becomes Megama^ra albida; Gammarus tenuis is called 

 Mirrddeutopux tenuis in the B. M. C, with the remark appended that " this species closely 

 resembles M. aiiomalus of the British coast ;" Gammanis fun-icornis, in the B. M. C. Mirra 

 furcicornis ; Gammarus tenellus in the B. M. C. Moira tenella ; Gumviarm fuegiensis, of 

 which Dana makes, and, as it were, in the same breath retracts, the suggestion that it may 

 "be the female of the G. tenellus," is called in the B. M. C. " Mrera Fuegiensis"; Gam- 

 marus quadrimanus, in the B. M. C. Mara quadrimanus ; Gammarus hrasiliensis called 

 " Gammarella Brasiliensis" in the B. M. C, although contrary to the definition of the 

 genus Gammarella the upper antennae are twice as long as the lower, and the third uropods 

 are evidently regarded as biramous ; Gammarus pugettensis the B. M. C. leaves unaltered. 

 Between the last and the following species Dana places a heading, " appendix to the genus 

 Gammarus." This section begins with Gammarus 1 peruvianus, called in the B. M. (J. 

 " Megamiera Peruviensis ; " this species was originally called by Dana Amphitlwi} peruviana, 

 and is here said to be " near the G. hrasiliensis in many characters ; " Gammarus 1 puhesams, 

 previously called Ampldtlwe pidieseens, is named in the B. M. C. Gammarella pubescens, but 

 it is difficult to see on what grounds, since the upper antennas are " almost twice as long as 

 the other pair," and the third uropods are not described ; Gammarus ? imlicus in the B. j\I. 

 C. is named "Megammra Indica;" Melita tenuicornis, doubtfully including what was 

 originally Amphitlwe. tenuicornis, male, and Amjjlritlwi' {Melita) incequistylis, female, is 

 given in the B. M. C. as Mcera tenuicornis, though with some doubt as to the genus, 

 because the species is described " us having no secondary appendage to the superior 

 antennae ; " Meera valida in the B. M. C. is named Melita ralida ; Miera setipes, in the 

 B. M. C. Melita setipes, is distinguished by the most trivial characters in the description 

 from the following species Meera anisorhir, of which the synonyms given are Gammarus 

 anisochir, Kriiyer, and G. (Masra) pilosus, Dana, this becoming in the B. M. C. Melita 

 anisocliir; Dana's figures, however, of the two species setipes and anisochir suggest the 

 possibility of more considerable differences than those which he mentions in the text. A 

 fuller definition than in the previous paper is then given of the new genus Dercothoe. 



" Epimenx. mediocres, 5tae submque bilobatse, itis wix breriores. Margo frontis lateralis jwcta 

 ocvlos ssepe valde saliens. Styli caudales postici simplieissimi, sat longi, ramo breri, 

 subeonico, apiee jmtdo refl&vo e quo spinis duabus brerissimis exseiiis. Antennx superiores 

 ssepius longiores, apjJendiculatae." He adds, " the posterior stylets are like those of Pyctilus, 

 and unlike those of any of the preceding genera. The carpus in the legs of the first jiair is 

 often as long as the head, and sometimes longer. The two very short spines at the apex of 

 the posterior stylets are full half as broad as long." 



The new genus Pi/ctilus is more fully defined as follows : — 



" Epimera; sat breres. Pedes \mi %lique jireliensiles, reliiiui mm preliensiles, secundarum digitu 

 i-articulat(i, mauii. 1-articii/atii. Antennx ehmgatie, secundee subtus primas affixee. Sti/li 



