EEPOET ON THE AMPHIPODA. 91 



Squilla pedata, forte etiam ventricosa ? Mulhvi." "Gen. IG. Caprella." wtli the note, 

 " ad hoc genus Astacus atomos, Pennant, Siiuilla lohata, Miiller, et Cancer Phasma Montagu 

 pertinent," but Leach declines to disentangle the confused synonymy. 



" SuLdivisio 2. Corpiis latum, Oculi in verticem siti. Antennai i-articulafie, superiores longiores, 

 articulo basilari paulo majore, seeundo tertioque eequalibus basilari jMululum minorihus, 

 ultimo minuto penultimo quadruple minore ; inferiores articulo basilari superiorum, breviores 

 articulo ultimo minuto. Pedes compressi valide unguiculati ; paria duo antica x'olUce 

 instructa; par anticum minimum ad capitis basin adnexum, carpo articulato, secundum majus 

 manu intus dentata, tertium et quartum coriaceo-membranacea, cylindrica, elongata, spuria. 

 Anus productus, tuberculis obscuris parvis. Bursa (uterus externus) valvulis quatuor 

 imbricata." Gen. 17. Laeunda, ^Yith. Ci/amus, Latreille, Lamarck, and Panope, Leach, for 

 synonyms. Larunda ceti, the only species. 



There are thus no new genera properly speaking in this paper, but Leach probably regarded 

 those -which had just been instituted by him in the appendix to his Article Crustaceology 

 in the Edinburgh Encyclopasdia as practically new. These are Dcxaminc, Ampitlwe, Pherusa, 

 Podocerus, Jassa. In the Encyclopsedia he refers to Mem. Wern. Soc, vol. ii., for Jassa, 

 but apparently by mistake, as the genus does not appear in that volume, and the reference 

 is not repeated in the LinuiEan Transactions. Atijlvs was instituted in the Zoolog. Misc., 

 vol. ii. Proto ajjpears here as a new genus, or at least without reference to any previous 

 work. It appears indeed in the appendix above-mentioned, but that appendix may have 

 been in fact contemporaneous in its production with the present " tabular view." 



Leach does not give any reasons for rejecting the earlier name Cyamus, Latreille, or his own 

 Panope, in favour of Larunda. Panope he may have thought too near to Panopca or 

 Panopsea emjjloyed among MoUusca in 1807. Cyamus he perhaps rejected as a name 

 already employed in botany, but Lutken points out that, so far as the Linnseau era is con- 

 cerned, its zoological use takes precedence of the botanical. 



1816. Leach, W. E. 



Anuulosa. Encyclopgedia Britannica. Supplement, pp. 401-453. 



The Annulosa are explained to comprehend five classes — Crustacea, Myriapoda, Arachnides, 

 Insecta, Vermes. The Crustacea are distinguished as having " Branchiae or gills for respira- 

 tion. Legs for motion." By " legs " are meant " those organs which actually perform the 

 functions of legs." A review is given of the earlier systems of classification for the 

 Crustacea, concluding with that adopted by Leach himself in the Linnean Society's Tran- 

 sactions, vol. xi. part 2, which was read in 1814, and published in 1815. This system is 

 here repeated, in English instead of in Latin, but otherwise as far as the Amphipoda are 

 concerned, practically nnaltered ; two or three immaterial observations are added, and in 

 Section III., the definitions of Divisio I. and its two subdivisions are omitted. In both 

 papers Phronima is sometimes spelled Phronyma, and in the English notes on Phronima 

 sedentaria Leach observes that " all authors have erred in giving but ten legs to this 

 animal." This is unjust to Forskal who attributes to the species "pedes utrinque decern : 

 paria enim septem thoracis septem articulis adhajrent." To Gainmarus pulex of his earlier 

 work. Leach, in this and the preceding paper, gives the name Gammarus aquaticus, as a 

 new species distinct from the Gammarus pulex of Latreille and Bosc, arguing from their 

 borrowed figures, which represent the hands much dentated within. That, however, is very 

 little to the purpose, since their figures are only taken from Ecisel's Squilla fluviatilis 

 without regard to the creature described. On Plate XXL, Mtlita palmata, Pherusa 

 fucicola, and Larunda ceti are figured. 



