REPORT ON THE CRUSTACEA MACRURA. 



551 



Alpheus longimanus, n. sp. (PI. XCVIII. fig. 4). 



Rostrum narrow and sharp pointed. Orbital lobes prominent but not pointed. 



First pair of antennae with the stylocerite broad, flat and disc-like, anteriorly produced 

 to a small, sharp pointed tooth ; the second joint of the peduncle is longer than the first, 

 and the third is shorter and terminates in two flagella, the longest of which is about two- 

 thirds the length of the body of the animal. 



The second pair of antennas carries a very minute tooth at the base, and a 

 scaphocerite that reaches as far as the extremity of the peduncle of the first pair of 

 antennae, but scarcely as far as that of the second pair. 



The first pair of pereiopoda is unequal on the two sides ; the larger, which is generally 

 on the right side, has the margins nearly parallel until near the base of the dactylos, where 

 a constriction takes place so as to form a tooth above and below. 



The pollex is produced anteriorly and curved at the point, the lateral margins being 

 elevated in the form of cusps that form a hollow or spoon-like space between them, into 

 which a blunt tooth or protuberance on the inner surface of the dactylos projects. The 

 smaller hand is long, slender, and subcylindrical, the fingers being nearly, and in some 

 instances quite, as long as the propodos. 



Habitat. — Off Yokoska, Japan, in from 5 to 20 fathoms. Four females, bearing ova. 



Stations 233, 233a, May 17, 19, 1875; off Kobe, Japan; depth, 8 to 50 fathoms; 

 bottom, sand and mud. Four specimens ; two males, one female, and one young. 

 Dredged. 



The body of the animal is generally robust, smooth, and even, having no groove or 

 carina on the dorsal surface of the carapace, except a small depression between the orbital 

 lobes and the rostrum, and another at the frontal margin external to the orbital lobes 

 (fig. 4c). 



The first pair of antennae has the first joint about the length of the rostrum and 

 supports an oval scaphocerite, tipped with a small tooth ; the second rather longer than 

 the first, and the third about half the length of the second; the flagella are very unequal, 

 the shorter and more robust is a little longer than the peduncle, the stouter portion 

 being produced to a rudimentary second branch, while the more slender flagellum is 

 nearly as long as the body of the animal. 



