GAMMARIDEA. 9H 



dales postici 2dis non similes, ramis saepe longis cum pilis raro spinulis ornatis, 

 apice non uncinatis. Antennae superiores saepius longiores. 



2. Styli caudales postici sive ramo uno longo alter o parvulo instructi, sive simplicissimi 



et apice non paulo rejlexi. 



* Antennse lmse non appendiculatse. 



G. 8. Photis, Kroyer.* — Epimerae magnae, 5tae 4tis non breviores et postiee pro- 

 fundius excisae. Styli caudales postici ramo interno rudimentario. 



G. 9. Melita, Leach, D. — Epimerae 5tse 4tis multo breviores (sic an semper ?) 

 Styli caudales uno ramo longo, sive subcylindrieo sive foliaceo, altero brevi vel 

 obsoleto. [Digitus in manus latus saepe claudens.] Antennae lmae saepius 

 longiores. 



** Antennse linns appendicular. 

 G. 10. M^era, Leach, D. — Epimerae et styli caudales postici ac in Melita. 



3. Styli caudales postici simplicissimi, ramo uno brevi et nudo, apice paulo refiexo et 

 spinas duas perbreves paulo exsertas gerente, 



G. 11. Dercothoe, Dana. — Epimerae mediocres, 5tae bene bilobatae, 4tis saepius 

 vix breviores. Pedes lmi 2dique digito uni-articulato confecti. 



G. 12. Ptctilus, Dana (Erichthonius, Edw.?) — Epimerae mediocres vel breves, 

 corpore lineari, subdepresso. Antennae longae, flagellis sat longis. Manus lmae 

 articulis 4to 5toque saepe instructae, digito uni-articulato; 2dae digito bi-articulato. 



291, and Beit, zur Faun. Norw., Act. Leop. xx.), includes those Gammari that have the 

 superior antennae the shorter — not of itself a proper basis for a genus. The eye is de- 

 scribed as reniform. 



The genus Eusirus of Krbyer, which is very near Gammarus, has the hands of the two 

 anterior pairs of legs large and equal, and the carpus is articulated with the upper margin 

 of the hand near its middle. The eye is reniform. The superior antennae have a short 

 appendicular branch, consisting of a minute joint. "Mandibula parva, apice bifurco, 

 dentato, flabello setarum marginis interioris, tuberculo molari transverso-elliptico denti- 

 bus minutissimis confectis formato ; palpus triarticulatus duplam fere aequat mandibulas 

 longitudinem. Sex branchiarum paria in maribus (annuli thoracici 2di-7mi), 4 lami- 

 narum in feminis paria (annuli 2di-5ti)." — Tids. [2], i. 501. 



* Tids., iv. 155, 1842. "Pes 5ti paris recurvatus, inversus, ungue rudimentari. 

 Epimera permagna, 5 paria anteriora ad marginem inferiorem setis sat longis instructa, 

 Stum eadem est ac 4tum altitudine, postiee profundius excisum. Lamina terminalis 

 interior pedis saltatorii 3tii paris rudimentaris." 



