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



quite unlike those of Lijsianassa. Five short filiform legs are represented, followed by 

 two very long ones, witli the first joint in each dilated, the rest slender. The pleon is 

 elongate. 



" Genere Lusyta, Nardo," follows, containing 



" Sp. 48. Lusyta algensis, Nardo ; Sinon. moderna cit. Cancer alr/ensis, Chier., sp. 60, 



fig. 76-79. Podoceros Leach.; Annot. aid. aWopera ms. del ChieregMn." Nardo 



says that Leach wrote with his own hand at the foot of the page containing the figure 

 given by Chiereghin, the generic name Podoceros, without indicating the species. Nardo 

 himself considers it to differ from Podoceros and also from Cerapus and Cerapodhia, 

 though like the two last, especially from its habit of living in a case. As the genus is not 

 separately defined, its characters must be derived from those which are said to be the essential 

 ones of the species : — " Estremita della testa un poco prolungantesi in rostro ; occhi posti 

 lateralmente alia base di tal rostro, alquanto peduncolati ; due lunghe anteune sorgono dal 

 dissotto del rostro terminate in punta ; hanno ciascuna nove articolazioni, e lungo il loro 

 lato inferiore dci lunghi sottilissimi peli ; al dissotto ne sorgono altre due piii corte, di sole 

 sei articolazioni, pelose anch' esse come le prime. 



" I primi due piedi sono grossetti, eguali, di cinque articolazioni, aventi il quarto pezzo pii; 

 grosso degli altri, e su di questo nasce un dito incurvato verso Fingiii, terminante in punta 

 ed atto a piegarsi sul lato inferiore del detto quarto pezzo. 



" Seguono cinque altri piedi per ogni lato. I tre primi paja sono sottili, composti di sei pezzi, 

 I'ultimo de'quali termina in una punta rivolta un poco verso ringiii. Gli altri due paja sono 

 \\R poco piu grossi e pih lunghi coH'ultimo pezzo die e piti ingrossato e parimenti 

 terminante in punta alquanto piti aguzza. Altri due paja di piedi aualoghi, sono posti 

 sotto I'ottavo pezzo. Nel quinto, sesto e settimo nascono invece che piedi delle ajspendici 

 membranose e filamentose. 



" La superficie del corpo e liscia e di color bianco candido." 



Its dwelling is said, on Chiereghin's authority to be on the leaves of the Zostera marina in tubes 

 shaped like a Cornucopia, formed of very fine threads agglutinated together, out of which it 

 thrusts its upper half, when seeking food, and by rapidly waving its arms and antennaa puts 

 the water into movement to draw small animals towards its mouth. The original Latin 

 definition is quoted, without the improvements upon the Latinity given in 1847, thus: — 

 " Cancer algensis, macrourus, thorace rostrato, vianihus aducfylis, i^edihus decern, termine 

 caudx triphylo." The figures 7, 7b, on plate xv., show the shape of the tube, slightly 

 curved, narrow at one end, widening gently to the mouth at the other extremity ; figures 

 7a, 7c, portray the animal very indistinctly, but with the upper autennas decidedly longer 

 than the lower, which is unsuitable to Podocerus. The description of "i primi piedi," i.e., 

 evidently the second gnathopods, suits the genus Gei-apus, but in the well-ascertained 

 species of that genus the tubes are straight, and open at both ends. J. V. Carus 1885, 

 gives Lusyta, Nardo, as a synonym of Podocerus, Leach, but without explanation and 

 without mention of the species algensis. 



The " Edriottalmi lamedipodi " are described on pages 323-.324. In this division Nardo gives 

 " Sp. 49.) Capkella linearis, Milne Edw. Cancel- linearis, L., Chier. sp. 61, fig. 80. 

 — — Olivi ; Zool. Adr. Oniscus Linearis, Latr., Martens ; Reise nach Venedig, p. 497." 

 He says that in 1847 he erroneously marked it as " Caprellx nova spiecies ?" He fmds that 

 it differs from Caprella monocantha [monacantlm], HeUer, by not having the spine at the 

 base of the second pair of feet, and some other trivial characters. Heller's species is 

 identified by Haller and Mayer with Caprella xquiUhra, Say ; Mayer gives up Nardo's 

 species as undecipherable. The fig. 4, on plate xv., however, will fairly suit Caprella 

 eequilihra, in which the spine above-mentioned has escaped the notice even of good 

 observers. 



