312 On the Classification of the Crustacea Choristopoda. 
G. 3. Leerocurgus, Zaddach.*— Antenne 1m: appendiculate. "Pedes 1mi bene 
subchelata, 2di manu carentes. 
B. PEDES 2Dr lMIQUE SUBCHELATI. 
* Antenne l1me non appendieulatz. 
^ 
G. 4. IeuruepiA, Rothke] D.—Epimere magne, 4te maxime, 5tis multo brevi- 
oribus et vix bilobatis. Styli caudales postici ramis duobus oblongis consimili- 
bus apice setigeris et non uncinatis instructi. Antennze lm: sepius breviores. 
G. 8. CEprcERus, Aróyer.i—Iphimedic affinis. Pedes "mi longissimi, fere fili- 
formes. Antenns lm: breviores. 
G. 6. AurnurrHoE, Leach, D.$—Epimers magne, 5tz maximzee, vix bilobatz lobo 
posteriore minimo. Styli caudales postici ramis duobus brevibus dissimilibus 
instructi, ramo externo apice recurvatim bi-uncinato, interno compresso apice 
non spinuloso sed pilis parce ciliato. JAntenns lm: sepissime longiores, 
** Antenne 1m: appendiculatz. 
G. 1. Gauxanvs, Fabr., D.|--Epimerz sive mediocres sive breves. Styli caudales 
postiei 2dis non similes, ramis szepe longis cum: pilis raro spinulis ornatis, apice 
non uncinatis. .Antenn: superiores sepius longiores. 
2. Styli caudales postici sive ramo uno longo altero parvulo instructi, sive simplicis- 
simi et apice non paulo reflexi. 
* Antenne lm: non appendieulatz. 
G. 8. Pnoris, Króyer.& —Epimere magnse, 5t: 4tis non breviores et postice pro- 
fundius excise. Styli caudales ramo interno rudimentario. 
* 'The genus Leptochirus, (Syn. Crust. Borus. Prodromus, 1844) is described by Zad- 
dach as having no appendicular branch to the superior antenne. But Fr. Muller states 
(Archiv für Naturgeschichte, 1848, xiv, 62) that there is a small one-jointed appendage 
in the Leptochirus pilosus. The legs of the 2nd pair are described as having no proper 
hand, but terminating as in the genus Talitrus. May the form be female only ? 
1 Beit. zur Fauna Norwegens, p. 85, Act. Leop. xx. .Dexamine of Leach, may 
perhaps be included here. 
The genus Zjyale of H. Rathke (Fauna der Krym, Mem. Acad. Imp. St. Petersb., 
iii, 1837, p. 318, pl. 5) contains no characters in its description by this author which 
do not apply equally well to species of Iphimedia. The description is as follows :— 
* Corpus elongatum, compressum. Antenne inferiores superioribus aliquantulum 
longiores; earum quzlibet e tribus articulis atque flagello composita. Oculi disci- 
formes. Pedes 14: duo eorum paria antica chelis monodactylis complanatis, 2di 
pàris multo majoribus. Stylorum abdominalium paria tria. Abdominis appendieula 
terminalis simplex, erecta, verruciformis." The posterior stylets are 2-branched 
though short; and the species (H. pontica) is thus distinct from the Allorchestes. 
I Tids.iv,155,1842. "* Frons in rostrum producta, plus minus acutum obtusumve, 
semper vero nodo pellucenti, ovali, flavo-rubescente turgidum. Oculi nulli?" * Pedes 
$ti 4tique paris validi ungue instructi lato laminari, quod quoque usu venit 5to 
6toque pari, quorum articulus 1mus dilatatus non est." 
8 Includes PAerusa of Leach. 
| -Amathia, Rathke (Fauna der Krym, Mem. Acad. Imp. St. Petersb., iij, 18377, p. 291, 
and Beit. zur Faun. Norw. Act. Leop. xx) includes those Gammari that have the superior 
antenn:e the shorter—not a proper basis for a genus. The eye is described as reniform, 
The genus Eusirus of Króyer is very near Gammarus, and it is doubtful whether 
it should be separated. Its habit however is somewhat different. 'The hands of thé 
2 anterior pairs of legs are large and equal, and the carpus is articulated with the 
upper margin of the hand near its middle. The eye is reniform. The superior antennze 
have a short appendieular branch, consisting of a minute joint. * Mandibula parva, 
apice bifurco, dentato, flabello setarum marginis interioris, tuberculo molari transverso- 
elliptico dentibus minutissimis confectis formato; palpus triarticulatus duplam fere 
zequat mandibulz longitudinem. Sex branchiarum paria in maribus (annuli thoracici 
2di—mi), 4 laminarum in feminis paria (annuli 2di-5t1)^—Tids. [2], 1, 501. 
«| Tids.iv, 155, 1842, * Pes Bti paris recurvatus, inversus, ungue rudimentari. 
Epimera permaegna, 5 paria anteriora ad marginem inferiorem setis sat longis in- 
structa, 5tum eadem est ac 4tum altitudine, postice profundius excisum. Lamina 
terminalis interior pedis saltatorii 3tii paris rudimentaris." 
The inversion of the 5th pair of legs is not a generic character. . 
TNT LL 
—— rase oh Ls ra t ei ii T i 
