the Species of Lucifer. 227 



of specimens, and as it is, in any case, wiser to emphasize 

 than to ignore possible differences. The most valuable con- 

 tributions to the subject have been made by Dana and by 

 Kemp, and I have in the main accepted their decisions in 

 the following synonymic list: — 



1. Lucifer typus, H. M.-Edw., 1837. 



Lucifer, J. V. Thompson, Zool. Researches, iv. p. 58, pi. vii. fig. 2 



(1829). 

 Leucifer typus, Ii. Milne-Edwards, Hist. Nat. Crust, ii. p. 469 (1837). 



Kemp thinks that this species is probably identical with 

 the L. acestra of Dana. The two are undoubtedly related, 

 but there are marked differences between Thompson's figure 

 and Dana's in respect of the sixth abdominal segment and 

 its limb. It seems best at present to maintain the specific 

 distinctness of L. typus until further research has rendered 

 it unlikely that there exists a species which corresponds 

 with Thompson's figure. In any case, the identification 

 cannot be sufficiently certain to justify the supersession of 

 Dana's name. 



Tropical N. Atlantic. 



2. Lucifer reynaudi, H. M.-Edw., 1837. 



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



pi. xxvi. fig. 10(1837). 

 Lucifer reipiaudi, Dana, U.S. Expl. Exped., Crust, i. "p. 672 (1852) ; 



Atlas, pi. xlv. tig. 1 (1855). 

 Lucifer ret/naudii, Kemp, Trans. Linn. Soc. Loud., Zool. (2) xvi. 1, 



p. 58 (1913). 



Indian Ocean. Sooloo Sea. 



3. Lucifer acestra, Dana, 1852. 



Lucifer acestra, Dana, U.S. Expl. Exped., Crust, i. p. 671 (1852) ; Atlas, 

 pi. xliv. fig. 9 (1855) ; Streets, Bull. U.S. Mug, vii. p. 122 (1877) ; 

 Faxon, Mem. Mus. Harvard, xviii. p. 214 (1895); Kemp, Trans. 

 Linn. Soc. Lond., Zool. (2) xvi. 1, p. 58 (1913). 



Throughout the warmer parts of the Pacific and Indian 

 Oceans from Mexico to Mauritius. 



4. Lucifer pacificus, Dana, 1852. 



Lucifer pacificus, Dana,"U.S. Expl. Exped., Crust, i. p. 673 (1852) ; 

 Atlas, pi. xlv. fig. 2 (1855). 



Tropical Pacific. 



5. Lucifer acicularis, Dana, 1852. 



Lucifer acicularis, Dana, U.S. Expl. Exped., Crust, i. p. 674 (1852) ; 

 Atlas, pi. xlv. tig. 3 (1855). 



Harbour of Rio Janeiro. 



