REPORT ON THE CRUSTACEA MACRURA. 279 



The second pair of antennas has a slightly tapering scaphocerite that reaches a little 

 beyond the extremity of the peduncle of the first pair, and a flagellum that is twice the 

 length of the animal. 



The mandible carries a two-jointed synaphipod, the second joint is narrower than the 

 first and reaches as far as the extremity of the peduncle of the second pair of antennae. 



The first pair of pereiopoda is armed with two teeth, one on the inferior margin of the 

 basis and another on the anteroinferior margin of the ischium. All the appendages of 

 the pereion are furnished with a basecphysis that decreases gradually to the posterior 

 pair of pereiopoda, where it is very reduced in size. 



The first pair of pleopoda in the female carries a rudimentary membranous branch 

 on the inner margin, near the distal extremity of the basisal joint. The succeeding 

 four pairs are subequally biramose. The sixth pair has the outer branch longer than the 

 inner, and is armed with a sharp tooth on the outer side at the extremity. 



Only a single specimen of this species, and that a female, was taken, and it differs 

 from all the other species in having the basisal branch attached to the several legs of the 

 pereion, although small, 3 T et much more important than the rudimentary ones which 

 they possess. 



Philonicus pectinatus, n. sp. (PL XXXVIII. ). 



Rostrum short, lanceolate, not reaching to the extremity of the ophthalmopod ; dorsal 

 margin armed with nine teeth, of which the posterior is slightly separated from the 

 others and implanted on the gastric region a little in advance of the cervical furrow. 

 Posterior dorsal surface of the carapace compressed but not carinated. Pleon carinated 

 from the fourth somite to the sixth, where it terminates in a small tooth. 



Telson dorsally longitudinally grooved, tapers to a point, and is distally armed on 

 each side with a strong tooth ; outer plates of the rhipidura nearly twice as long as the 

 telson. 



Ophthalmopoda with the ophthalmi reniform. First pair of antennae having the pros- 

 artema shorter than, and the stylocerite as long as the ophthalmopod. Second pair of 

 antennae having the scaphocerite longer than the peduncle of the first pair of antennae, and 

 narrowing to the distal extremity, which is rounded and carries a tooth on the outer angle. 



All the other parts of the specimen are much broken except the pleopoda, the first 

 pair of which is furnished with a petasma {pp) that carries a series of curved teeth on 

 each side like a comb, from which the specific name is derived. 



Length (male), 38 mm. (To in.). 



Habitat.— Station 188, September 10, 1874; lat. 9° 59' S., long. 139° 42' E.; 

 Arafura Sea, south of Papua ; depth, 28 fathoms ; bottom, green mud. One specimen ; 

 male. 



