EEPORT ON THE CRUSTACEA MACRURA. 787 



Palasmonella orientalis, Dana (PI. CXXVIII. fig. 4). 



Palmmonella orientalis, Dana, U.S. Explor. Exped., Crust., p. 582, pi. xxxviii. figs. 4a-d. 



Carapace less than one-third of the length of the animal, anteriorly produced to a 

 slender rostrum, that is armed on the upper surface with six teeth and on the lower with 

 a small tooth near the apex. 



Pleon smooth. 



Telson long, narrow, and tapering. 



Length, 5 mm. (0"2 in.). 



Habitat— Station 200, October 23, 1874; lat. 6° 47' K, long. 122° 28' E.; off 

 Sibago, Philippine Islands ; depth, 250 fathoms ; bottom, green mud. One specimen ; 

 probably taken at or near the surface. Trawled. 



The carapace is smooth and anteriorly produced to a rostrum that is subequal in 

 length with the dorsal surface of the carapace ; it is armed above with six equidistant 

 teeth, the posterior of which is above the orbital margin and the anterior close to the 

 apex of the rostrum, and below with one small tooth near the distal extremity, the rest 

 of the lower margin being smooth and parallel with the upper ; beyond the orbit on the 

 frontal margin is a first antennal tooth, and, according to Dana, another tooth is situated 

 in nearly the same parallel line, and therefore must be the hepatic tooth. 



The pleon is smooth and the somites subequal, the sixth being longer than the 

 preceding, and the telson subequal in length with it. 



The ophthalmopoda are pyriform and rather large. 



The first pair of antennas is furnished with a short stylocerite, has the peduncle 

 subequal in length with the rostrum, and supports two moderately robust flagella, 

 the outer of which after two rather large articuli divides into two unequal branches, the 

 longer about half the length of the animal, the shorter about one-fourth the length of 

 the other, but more robust, and supporting a series of membranous or sensory cilia. 



The second pair of antennae is subequal in length with the animal, and supports a 

 scaphocerite that reaches beyond the distal extremity of the rostrum. 



The second pair of gnathopoda is short, five-jointed, and furnished with a basecphysis 

 that reaches as far as the carpal articulation ; the terminal two joints are more slender 

 than the preceding and fringed with hairs, of which those at the distal extremity are 

 stiff and spine-like (fig. 4i). 



The first pair of pereiopoda is long, slender, and chelate. The second pair is longer, 

 larger, and similarly formed. The three succeeding pairs are subequal in length, 

 moderately robust, and have the carpos distally produced beyond the propodal articula- 

 tion ; the propodos is cylindrical, slightly curved, and fringed with small fasciculi of 

 hairs ; the dactylos is curved and terminates in two unequal ungues. 



