NO. 2 MUD SHRIMPS SCHMITT II 



of the merus is interrupted close to the posterior end by a conspicuous 

 narrow U-shaped notch, at the upper extremities of which the dorsal 

 margin of the joint forms a blunt tubercle. 



The ventral margin of the ischium is, beginning near the hinder end, 

 finely and for the greater part rather evenly denticulate, the denticles, 

 however, gradually increasing in size anteriorly, the last two or three 

 being larger, the last of these very large comparatively, and forming 

 rather a tuberculiform tooth almost half a millimeter long and distally 

 obscurely bilobed ; in advance of this tooth the lower margin is blunt- 

 ridged; above on the outer face, and shorter than the denticulated 

 portion of the lower margin of the ischium, is an obscure, blunt ridge. 



When both chelipeds are moderately extended to about the same 

 degree, the fingers of the smaller reach scarcely half their length beyond 

 the distal margin of the carpus of the larger. The ischium is about as 

 long as the merus and a little longer than the carpus or upper margin 

 of palm, but only four-sevenths the length of the movable finger. The 

 upper margin of the dactylus is ridged and grooved, the prehensile 

 edges of both fingers are wide and somewhat hollowed out and the 

 movable one is furnished with two anteriorly converging lines of ob- 

 scure, small tubercles ; the extreme tips are somewhat abruptly con- 

 stricted to form conical spinous tips so that there is apparently a blunt 

 tooth at the anterior extremity of the outer moiety of each fairly broad 

 prehensile edge ; when closed, the tips of the finger reach about equally 

 far forward ; there is a sizable gape between them. The palm is 

 rounded above, cristate below, except on the distal half of the fixed 

 finger, carpus blunt above, cristate below, superior and inferior distal 

 angles subacute, merus blunt-ridged above and below ; ischium blunt 

 above, with finely denticulate margin below ; the ischium and merus 

 are about of the same length measured on the upper border, either a 

 little longer than the carpus, about one-third longer than the upper 

 border of the palm, and a little less than two-thirds the length of the 

 movable finger. 



The inner face of the ischium of the third maxilliped (pi. 2, fig. 8) 

 carries a smooth, blunt, yet well-formed, carina wholly without spinous 

 armature, or tiny scalelike excrescences. 



Telson somewhat rectangular, about one and one-third times as long 

 as wide, little less than half as long as the sixth somite. Posterior 

 margin three-lobed, shallow, median lobe occupying more than one- 

 third of the posterior margin, and the gently curved lateral angles 

 carried evenly and smoothly around to their respective sides to merge 

 with lateral margins of the telson ; dorsal surface evenly convex in 

 both directions ; across the dorsum of the telson a little way before the 



