CRUSTACEA CASPIA. 295 



described iu detail, as they in some poiuts differ ratlier markedly from those 

 in the Gammari^ce. 



The anterior lip (PI. XX, fig. 5) is broadly quadrangular in form, with 

 a dentiform projection in front. The terminal edge is very slightly emargi- 

 nated and finely ciliated. 



The posterior lip (fig. 6) is rather large, with distinctly developed inner 

 lobes. The outer lobes are narrowly rounded at the tip, which is edged with 

 delicate cilia, and project outside to a narrow lappet. 



The mandibles (figs. 7, 8) are short and stout, with a well-developed 

 molar expansion. The cutting edge is in both mandibles divided into 2 super- 

 posed lamellae, the outer of which is distinctly dentated, wliereas the inner is 

 very narrow, spiniform, especially on the right mandible. Behind the cutting 

 edge there occur on the left mandible 3, on the right only 2 ciliated spines. The 

 palp .(see fig. 7) is very small, and composed of only 2 joints of about equal 

 length, and generally forming together a strong geniculate bend. The 1st 

 joint has at the end a single spiniform seta, and a similar, though somewhat 

 more slender seta issues from the tip of the very narrow, conically tapering 

 terminal joint. 



The 1st pair of maxillae (fig. 9) would seem wholly to want the basa 

 lobe. The masticatory lobe is narrowly truncated at the end, which carries 

 several slender spines. The palp is well developed and biarticulate, with the 

 terminal joint somewhat expanded distally and armed at the tip with a 

 number of small spines. 



The 2nd pair of maxilhx; (fig. 10) are rather fully developed, being 

 scarcely smaller than the 1st pair. The inner lobe is somewhat curved and 

 narrowed distally, having at the tip a dense clothing of small si)ines and 

 along the inner edge a regular row of slender, ciliated setie. The outer lobe 

 is considerably larger than the inner and somewhat expanded distally, with 

 a dense brush of slender spines on the obtusely truncated tip. 



The maxillipeds (fig. 11) exhibit all the pertaining parts well developed. 

 The basal lobes are of a somewhat unusual form, being conically tapered 

 distally, and having along the inner edge a row of slender curved seta). The 

 masticatory lobes are very much elongated, narrow linguiform in shape, and 

 fringed along the inner edge with numerous very delicate bristles. The palps 

 are slender, and rather densely setiferous, with the joints somewhat laminar. 

 The last joint is comparatively small and narrow, and the dactylus is ex- 

 tremely minute, knob-shaped, and setous at the tip. 



The anterior gnathopoda (fig. 1 2) are comparatively slender and feeble 

 in structure. The basal joint is i-ather narrow, though gj'adually somewhat 

 widening distally. The ischial joint is short and thick, and carries below a 



^u3.-MaT. CTp. 203, 21 



