No. 402.] MWORTH-AMERICAN INVERTEBRATES. 505 
KEY TO THE GENERA OF THE FAMILY MAIID&. 
A. Basal joint of antennz extremely slender throughout its length and 
usually long. Eyes without orbits and not concealed. 
B. Carapace elongate, narrowed in front. External maxillipeds 
somewhat pediform, with the palp large and coarse, and the 
merus often narrower than the ischium. Basal joint of antenna 
usually subcylindrical. 
C. Rostrum extremely long. Dactyli of ambulatory legs longer 
than the propodi. 
D. Carapace smooth, even aere Antenne concealed 
beneath the rostrum . .. Stenorynchus 
D’. Carapace uneven above. jme ree flagellum ex- 
posed . Metoporhaphis 
C. Rostrum short. Dactyli d EA ica shorter than the 
ropodi.. ss Podochela 
5. Carapace usually lobtlanpaler Eo faaxitfipeds with the 
merus at least as broad as the ischium, and the palp small. 
Basal joint of antenne flattened or concave ventrally. 
C. Rostrum simple, or with two short spines or lobes. 
D. No postocular spine or tooth. 
E. Chelipeds not much elongated, palms inflated. Ros- 
trum emarginate ZEpinus 
E’. Chelipeds much DURER with pams ‘long and 
; slender. Rostrum simple . c. Erileptus 
D’. A postocular spine or tooth. 
E. Eyes long andslender . . . > Arachnopsis 
E'. Eyes not long and slender. 
F. Inner crest of basal antennal joint very promi- 
nent and projecting downward at right angles 
to the outer crest. 
G. Postocular tooth pointing forwar d. 
ostocular tooth UN close to the 
eye . Dasygyius 
u. Postocular tooth not fitting close to 
eye nachoides 
G'. Paini tooth Aoin uident 
Collodes 
F’. Inner crest of basal antennal joint, when present, 
not projecting downward at right angles to 
the outer crest. 
G. Rostrum simple . . . . . Anasimus 
G'. Rostrum bifid. 
H. Spine of basal antennal joint not 
advanced to the line of the front. 
