310 |. On the Classification of the Crustacea Choristopoda. 
Fam.IV. ORCHESTIDJ/E.* 
Saltatoriz, pedibus nullis lateraliter porrectis. Corpus compressum, 
epimeris magnis. Abdomen appendicibus normale. JAntennse non 
bene pediformes. Styli caudales lmi 2dique biramei; 3tii simplices, 
brevissimi et ultra 2dos non prolongati. Mandibule non palpigerz. 
Maxille lraz palpo sive parvulo et l-articulato sive obsoleto instruetz. 
G. 1. OncnmrsrrA——Maxillipedes non unguiculati. Antenne 1ms basi 2darum 
breviores. Epimerz 5tz 4tis parce breviores. 
Subgen. 1. TArrrgvs.—Pedes 1mi maris femincve manu non instructi. 
Subgen. 2. 'ALoncuEsrIA, J).—Pedes lmi maris ac in Talitro, femine manu 
parvulà instructi. 
Subgen. 3. Oncnxsrra.—Pedes lmi maris femineque manu plus minusve 
instructi. 
G. 2. ArroncnuesrESs, Dana.—Maxillipedes unguiculati. Antenne lmz minores, 
basi 2darum longiores. Epimerz 5tze 4tis scepius multo breviores. 
Fam. V. GAMMARIDJE. 
Saltatoriz vel natatorize, pedibus nullis lateraliter porrectis. Corpus 
ssepius compressum, raro subdepressum, epimeris sive magnis sive par- 
vis. Styli caudales laxiores, duobus ultimis oblongis szepiusque ultra 
2dos prolongatis, raro simplicibus. Mandibule szpissimé palpigerz. 
Maxilla 1mz palpo 2-3-articulato (rarissimé l-articulato) instruct. 
I]. rEpESs 1O PosTiCcI NON PREHENSILES. 
Subfam. l1. STEGOCEPHALINZE.—Antennz breves, superiores basi crasss. 
Mandibulz acie denticulatá instructz, palpo brevi uniartieulato intus dentato.  Epi- 
mera permagns. 
G.1. SrEcocEPBHALUS, Áróyer.—Epimere 4te maxime, btis parvis. Antenne 
superiores appendiculate. Pedes lmi 2di manubus carentes. [Pedes bti 83tii 
4tique directione similes.] 
Subfam. 2. LYSIANASSINJE.—Antenne breves, superiores basi crasse.  Man- 
dibule apice parce dentate, acle vix instructe, palpo 2-3-articulato. Maxillipedes 
lamellis internis grandibus. Epimers permagns. 
1. Pedes lmi 2dique non subchelati, 9dis parvulis interdum exceptis. 
G-1. LxsrawassA, dw.—Antennz superiores appendiculatz. 
G.92. Pnuris, Guerin.—Antenng superiores non appendieulateze. 
9. Pedes lmà subchelati, 9dis non subchelatis. 
G. 3. Orrs, K.]—Antenne superiores appendiculatze. Pedes lmi crassé chelati, 
2di debiles. 
* The author gives a different arrangement of the species of Orchestide from 
that published in this Journal, [2], viii, 135 and ix, 295, and rejects the genus Tali- 
ironus there instituted. He follows Fr. Müller (Archiv f. Nat., 1848, 53) in consid- 
ering the Talitri and Orchestisz as forming a single genus, his recent investigations 
confirming this view. The Gammaridz also are rearranged. 
1 Kroyers Nat. Tids. iv, 150, 1842.  * Caput oculis ut videtur destitutum." 
l Tids.iv, 149. * Pedes lmi paris chelis armati portentose magnitudinis, Reli- 
qua cum genere Anonyce ferme convenuint." 
