's RIJKS MUSEUM VAN NATUURLIJKE HISTORIE — LEIDEN. 109 



carpus 1, propodus 1,45, in the female: merus 1,8, carpus 1, propodus 1,4, 

 dactylus 0,75. Telson 4-times as long as the posterior margin is wide, 

 dorso-lateral spinules large, 0,26 mm. long. 

 Length of both specimens 20 mm. 



Alpheas ear y dactylus n. sp. 



1 adult male and 1 ova-bearing female from Java. 



Closely resembling A. Euphrasy ne de Man from the Java Sea, the 

 Flores Sea and Bangkok, but distinguished by the following. Rostrum 

 a little shorter, not yet reaching to the middle of the visible part of 1st 

 antennular article. Rostral carina distinct, separated by broad, rather deep 

 grooves from the orbital hoods, rounded above and passing at the end 

 of the hoods into the smooth surface of the carapace. Telson like in 

 A. Eiiphrosyne, but the anterior pair of dorso-lateral spinules implanted 

 a little before the middle, the posterior pair also a little more forward 

 and the uropods slightly longer in proportion to their width. Antennae 

 and antennulae exactly like in A. Eiiphrosyne, also the external maxil- 

 lipeds. Larger cheliped only differing from that of A. Eiiphrosyne by 

 the palm of the chela being a little higher in proportion to the length. 

 Fingers of the small chela of the male almost quite as long as the palm 

 and the flattened upper surface of the dactylus comparatively broader, 

 half as broad as long. Palm and fingers of the small cheliped of the 

 female less high in proportion to their length : in the adult female of 

 A. Eiiphrosyne the small chela is 16,5 mm. long, the palm 6 mm. long 

 and 3,8 mm. high, in the female of A. eurydactylus these numbers are, 

 in the same succession, 14 mm., 6 mm., 3 mm. 



Male long 40 mm., female 45 mm. from apex of rostrum to tip 

 of telson. 



1er s eke, January 1920. 



