910 CRUSTACEA. 



Gr. 3. Leptochirtjs, Zaddach* — Antennae lmae appendiculatae. Pedes lmi bene 

 subchelati, 2di maim carentes. 



B. Pedes 2di ]mique subchelati. 

 * Antennas lmse non appendiculatse. 



Gr. 4. Iphimedia, Rathkerf D. — Epimerae niagnae, 4tae maximae, 5tis multo bre- 

 vioribus et vix bilobatis. Styli caudales postici ramis duobus oblongis consimili- 

 bus apice setigeris et non uncinatis instructi. Antennae lmae saepius breviores. 



Gr. 5. (Edicerus, Kr'6yer.\ — Iphimedige affinis. Pedes 7mi longissimi, fere fili- 

 fornies. Antennas lmae breviores. 



Gr. 6. Amphithoe, Leach, D.§ — Epiinerae magnae, 5tae maximae, vix bilobatae lobo 

 posteriore mininio. Styli caudales postici ramis duobus brevibus dissimilibus 

 instructi, ramo externo apice recurvation bi-uncinato, interno compresso apice non 

 spinuloso sed pilis parce ciliato. Antennas lmae ssepissime longiores. 



** Antennas lmse appendiculatae. 

 Gr. 7. GtAMMArus, Fabr., D.\\ — Epiinerae sive mediocres sive breves. Styli cau- 



* The genus LeptocMrus is described by Zaddach (Syn. Crust. Boruss. Prodromus, 

 1844), as having no appendicular branch to the superior antennae. But Fr. Muller states 

 (Archiv far Naturgeschichte, 1848, xiv. 62) that there is a small one-jointed appendage 

 in the Leptochirus pilosus. The legs of the second pair are described as having no 

 proper hand, but terminating as in the genus Talitrus. May the form be female only ? 



f Beit, zur Fauna Norwegens, p. 85 ; Act. Leop. xx. Dexamine of Leach, may per- 

 haps be included here. 



The genus Hyale of H. Rathke (Fauna der Krym, Mem. Acad. Imp. St. Petersb., iii. 

 1837, p. 378, pi. 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. Antennae inferiores superioribus aliquantulum 

 longiores; earum quaalibet e tribus articulis atque flagello composita. Oculi disciformes. 

 Pedes 14 ; duo eorum paria antica chelis monodactylis complanatis, 2di paris multo 

 majoribus. Stylorum abdominalium paria tria. Abdominis appendicula terminalis 

 simplex, erecta, verruciformis." The posterior stylets are two-branched, though short ; 

 and the species (H. pontica) is thus distinct from the Allorchestes. 



% Tids., iv. 155, 1842. "Frons in rostrum producta, plus minus acutum obtusumve, 

 semper vero nodo pellucenti, ovali, flavo-rubescente turgidum. Oculi nulli? Pedes 

 3tii 4tique paris validi, ungue instructi lato laminari, quod quoque usu venit 5to Gtoquc 

 pari, quorum articulus lmus dilatatus non est." 



§ Includes Pherusa of Leach. 



|| AmaihJa, Rathke (Fauna der Krym, Mem. Acad. Imp. St. Petersb., iii. 1837, p. 



