30 



Gen. 1. Notodelphys, Allman, 1847. 



Generic Characters. Body more or less elongated, and in female con- 

 spicuously dilated in the middle on account of the greatly expanded matrical 

 part; integuments rather soft and flexible. Cephalic segment not very large, 

 and produced in front to an obtuse deflexed rostral prominence. The 2 

 succeeding segments in both sexes well defined and separated by deep lateral 

 incisions. Incubatory pouch in female broad, flattened, more or less advancing 

 over the base of the tail. The latter perfectly cylindrical in form, with the 

 1st segment in female scarcely larger than the succeeding ones, in male some- 

 what swollen and generally containing 2 oval spermatophores. Caudal rami, 

 as a rule, finely ciliated on both edges, ?nd each carrying at the tip 4 well 

 developed and somewhat diverging plumose setae, being moreover provided 

 with 2 small bristles, the one attached to the outer edge, the other to the 

 dorsal face, near the inner corner. Eye comparatively small, but easily observ- 

 able in the living animal, being provided with 2 lateral lenses imbedded in a 

 bright red pigment. Anterior antennae in female gradually tapered distally, 

 and generally composed of 15 joints clothed with comparatively short, but 

 distinctly ciliated setae; those in male having the number of joints somewhat 

 reduced, and exhibiting between the penultimate and antipenultimate joints a 

 well marked hinge. Posterior antennae only composed of 3 distinctly defined 

 joints, the first 2, representing the basal part, somewhat compressed and 

 separated by an oblique suture, at the end of which outside 2 juxtaposed 

 plumose setae are attached; terminal joint very movably articulated to the basal 

 part, and linear in form ; apical claw accompanied by a number of short 

 curved setae. Anterior lip projecting at the end into 2 triangular lappets. 

 Mandibles with the masticatory part lamellarly expanded and divided at the 

 end into several unequal teath; palp well developed, biramous. Maxillae with 

 all their constituent parts distinctly defined. Anterior maxillipeds with the 1st 

 basal joint very large and massive, exhibiting inside 3 or 4 short setiferous 

 lobes; 2nd basal joint much narrower, and armed at the end inside with a 

 strong claw-like spine accompanied by a slender seta; terminal part thin, 

 3-articulate. Posterior maxillipeds much smaller than the anterior ones, and 

 3-articulate, 1st joint much the largest and provided inside with several short 

 plumose setae arranged in 2 groups, each of the other 2 joints armed with a 

 slender incurved spine, that of the terminal joint accompanied by 2 small setae. 

 Natatory legs with the basal part broad and flattened, rami in all the pairs 



