86 CEYLON PEARL OYSTER REPORT. 



(Station XLVIIL), 3 specimens; Coral reef, Manaar (Station LTV.), 2 specimens ; oft 1 

 Mutual Island (Station LXVIL), 1 specimen. 



Rostrum well developed, reaching to the end of the 1st segment of the antennular 

 peduncle. The 2nd segment of the antennular peduncle is slightly longer than the 

 1st or 3rd, which are subequal. The antennal peduncle and scale are equal in length 

 and slightly longer than the antennular peduncle. In the Ceylon specimens the 

 large chela is massive and the palm is broad. The meropodite is spiny on its inferior 

 border. 



The 3rd pair of legs has the ischiopodite with a single spine. The meros is smooth 

 except for a small spine at the posterior distal border. The carpos is smooth. The 

 propodite bears five pairs of spines. The dactylopodite is half the length of the 

 propodite and slightly curved. 



General distribution : Pacific, Japan, Maldives, Ceylon. 



Alpheus pareucheirus, Coutiere. 



Alpheus pareucheirus, Coutiere, ' Fauna of Maid, and Lace.,' p. 906, 1905. 



Locality : Haul 6, south of Adam's Bridge (Station LIV.), 1 specimen. 



The antennules and antennse do not differ greatly from those of the preceding 

 species. Their peduncles are not so stout. The rostrum is only two-thirds as long as 

 the 1st segment of the antennular peduncle. The large chela differs in having the palm 

 grooved on both sides. The meropodite is smooth. In the 3rd legs the ischiopodite 

 does not bear a spine. The meropodite is smooth and not so robust as in the previous 

 species. The carpos is smooth and the propodite bears 8 long spines on the posterior 

 border. The dactylopodite is long and slightly curved. 



General distribution : Maldives and Ceylon. 



Alpheus bis-incisus, var. malensis, Coutiere. 



Alpheus bis-incisus, var. malensis, Coutiere, ' Fauna of Maid, and Lace.,' p. 910, 1905. 



Locality : Cheval Paar (Station LXIX.), 1 specimen. 



The rostrum is triangular, and separated from the orbits by two well-marked 

 grooves. It reaches to the middle of the 1st segment of the antennular peduncle. 

 The 1st and 2nd segments of the antennular peduncle are subequal and slightly 

 longer than the 3rd. The antennular scale almost as long as the 1st peduncular 

 segment. The peduncle and scale of the antennal are equal in length and slightly 

 longer than the antennular peduncle. 



I have placed this specimen in Coutiere's variety merely on the characters of the 

 rostrum and antennae. The large chela and most of the legs are missing. 



General distribution : Maldives and Ceylon. 



Alpheus bis-incisus, var. stylisostris, Coutiere. 



Alpheus bis-incisus, var. stylisostris, Coutiere, 'Fauna of Maid, and Lace.,' p. 911, 1905. 

 Locality : Coral reef, Gulf of Manaar (Station LIV.), 1 specimen. 



