NEW PHILIPPINE FIDDLER-CRAB. 93 



defined, outer one most prominent, a well-marked elongated 

 depression between them. Fingers rather slender, strongly 

 flattened, minutely granular; both have a longitudinal groove 

 on the external surface, but that in the fixed finger is the deeper ; 

 fixed finger tapering, nearly straight, hooked at the top, smooth 

 on lower margin and denticulate on inner margin; movable 

 finger slightly arcuate, bearing 2 strong spines on inner margin, 

 one at the tip and the other about one-fourth of the length of the 

 inner margin from it; most individuals also have a strong den- 

 ticle on the inner margins of each of the fingers about one-third 

 of the distance from the proximal end. Merus of last pair of 

 legs somewhat foliaceous. 



Color of living male. — Dorsal surface of carapace, dark brown 

 (65)' (almost black) with a transverse yellowish-white (141) 

 band back of the front and sometimes another spot of the same 

 color in the center of the back; eye-stalks light brown (137). 

 Large chela with fingers and inside of palm white, outside of 

 palm whitish or green above (341) and fuscous (102) below. 

 Other walking legs gray (222) ; back of merus of last pair of 

 legs white; abdomen bluish (402). 



The above description was taken from 69 males and 8 females, 

 collected May 22, 1911, at an estuary three blocks south of the 

 Philippine Medical School, Manila, P. I. The 10 largest males 

 gave the following average measurements: Length of carapace, 

 14.64 mm; breadth of carapace, 24.40; length of chela 40.3. 

 This species closely resembles U. diissumieri ( Milne-Edwards ),- 

 but can be distinguished from it by the constant presence of a 

 tooth on the inner margin of the movable finger near the tip, 

 by the well-marked lines bounding lateral borders of the dorsal 

 surface, and by the less salient character of the 2 oblique ridges 

 on the inner surface of the palm. 



Miss M. J. Rathbun has kindly compared two specimens of 

 this species with specimens of 13 narrow-fronted species from 

 the Indo-Pacific region in the United States National Museum. 

 She reports that U. rathhunse is most nearly related to U. urvillei 

 (Milne-Edwards) and makes the following observations: 



Shape of carapace much as in U. urvillei. The orbital margin is a little 

 more oblique. Frontal furrow longer, not triangular and sharp pointed at 

 the extremity as in urvillei, but slightly spatulate. The accessory line of 

 granules above the lower margin of the orbit is much shorter, occupying 



' The numbers following colors refer to Klincksieck, P., et Valette, T. Code 

 des couleurs. Paris (1908). 



^ For references, see Alcock, Jour. Asiat. Soc. Bengal (1900), 69, 362. 



