REPORT ON THE CRUSTACEA MACRURA. 443 



Subfamily Luciferin^e. 



This subfamily is formed to receive those Sergestidae that have no branchiae attached 

 to the pereion ; in which the two anterior pairs of pereiopoda are not chelate, and the 

 third pair has the chelae reduced to a more or less imperfect condition ; in which 

 the ova are carried beneath the pereion, but appear not to have any special means of 

 attachment, and in which the brephalos is hatched in the Nauplius form. Of this sub- 

 family there is known to exist only a single genus. 



Lucifer, Vaughan Thompson. 



Lucifer, Vaughan Thompson, Zool. Researches, p. 58, pi. vii. fig. 2, 1829. 

 Leucifer, Milne-Edwards, Hist. Nat. Crust., torn. ii. p. 469. 

 Lucifer, Dana U.S. Explor. Exped., Crust., p. 668. 



Animal long, slender, and laterally compressed. Cephalon cylindrical, and produced 

 to a great length anteriorly to the mandibles, so that the antennae and ophthalmopoda 

 are removed considerably from the oral and other appendages. The pereion is short and 

 dorsally covered with a small receding carapace. The pleon is very long, being about 

 two-thirds the length of the animal, and has the five anterior somites subecmal, 

 whereas the sixth is about twice or thrice the length of either of the preceding. 



The telson is narrow, compressed and tapering, differing more in sexual than in 

 specific form. 



The ophthalmopoda are long, narrow, and terminate in round, bulbous ophthalmi. 



The first pair of antennae (PL LXXIX., b) has a three-jointed peduncle and a single 

 slender flagellum, and carries within the basal portion of the first joint a well-defined 

 acoustic organ (or otolith). 



The second pair (c) has the joints of the peduncle closely united ; the first supports a 

 long, slender phymaeerite, and the second a long, slender, somewhat styliform scapho- 

 cerite ; and the terminal joint is long, robust, and supports a long, slender flagellum. 



The distance from the second pair of antennae to the epistoma is greater than from 

 that to the posterior extremity of the pereion, and these together form about one-third 

 the length of the animal. 



The mandibles do not carry any synaphipod, and have the margin of the psalisiform 

 blades serrate. 



The first pair of siagnopoda (e) is three-lobed, two lobes being on the inner side, one of 

 which is broad and fringed with several strong spines, the other narrow and furnished 

 with a few slender spines or hairs ; and one on the distal surface that is narrow, cylindrical, 

 and free from ornamentation. 



The second pair (/) consists of four foliaceous lobes ; the two basal are produced inwards, 



