Figure 183. — Tips of right first pleopods of male xanthids; A, Glyptoxantliiis erosus (Stirupson), medial view; B. 

 Carpoporus papnlosus Stimpson, medial view; C, Rhithropanopeus harrisii (Gould), medial view; D, Hexa- 

 pannpcus angustifrons (Benedict and Rathlmn), medial view; E, Hexapanopeus paulensis Rathlmn, medial view; 

 P, Neopanopc texana texana (Stimpson), medial view; G, Ncopanope texana sayi (Smith), medial view;' 

 H, Leptodius agassizii Milne Edwards, medial view; I, Micropanope exwithiformis (Milne Edwards), abdominal 

 view; J, Micropanope nuttingi (Rathbun), medial view; K, Eiirypanopeus aobreviatus (Stimpson), medial view; 

 L, Eurypanopeus depressus (Smith), medial view; M, Panopeus herbstii H. Milne Edwards, medial view; N, Pano- 

 peus occidentalis Saussure, medial view; O, Eurytium limosum (Say), medial view; 0.5 mm. indicated for all 

 ■figures, except I and J twice this magnification, and O one-half this magnification. 



Recognition characters. — Carapace broad, ap- 

 proximately 1.5 times as wide as long, quite convex 

 from front to back, nearly plane from side to 

 side ; surface smooth to eye but under a lens finely 

 granulate, granulations coarser near frontal and 

 anterolateral margins. Front approximately one- 

 fourth width of carapace, divided into two lobes 

 by a median notch giving rise to a shallow groove 

 disappearing over gastric region. Orbital margins 

 somewhat elevated; external orbital tootli coa- 

 lesced with Hist tootli of anterolateral border, di- 

 vision between these teeth indicated by a shallow 

 h. Anterolateral teetli witli raised margins, 

 second and third teeth rounded at tip, fourth more 

 prominent and subacute. 



Chelipeds massive, unequal, and dissimilar, 

 more so in male than in female .;. merus with 

 coarsely tuberculate superior border and a distal 

 spiniform tooth; carpus with a narrow internal 

 spine, not grooved; fingers pointed, deflexed, with 

 large basal tooth on major dactyl. 



Measurements. — Carapace: length, male, 2\ 

 mm. ; width, 36 mm. 



Color. — Carapace brilliant purplish blue, dark 

 gray, or black; carpus and hand bluish; proximal 

 upper half of dactyl pink or purple; remainder of 

 fingers porcelain white; lower portion of che- 

 lipeds, and also carpal teetli, yellow or orange; 

 color of fingers not continued on palm. 



Habitat. — This primarily tropical species lives 

 in muddy or marshy banks a bit below t lie high- 



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FISH AND WILDLIFE SERVICE 



