50 



of Lucifer and their Distribution", in which he gave a tabular view of the forms, and besides 

 synonymy with notes on each species. The material examined by him seems to have been 

 proportionately small, and many of the characters used in the key are based on the figures or 

 descriptions in the literature. But most of these characters are either wrong or for some other 

 reason of slight or no value. He adopts L. Reynaudii M.-Edw. and the three species established 

 by Dana, even L. acicularis based on semi-larval characters; furthermore he describes a new 

 species, L. inermis, which is only a synonym to L. Hanseni Nobili (he had overlooked Nobili's 

 above-named paper, but in 191 6 in another paper he withdraws L. inermis as a synonym); 

 finally he establishes 5 new species on differences in the descriptions or figures published by 

 earlier authors; the result is that he has in all 11 species. As J. V. Thompson has figured a 

 Lucifer^ and Dana's L. acestra is without any rostrum, he considers this feature as a real 

 specific character, though it is only an error, as a rostral process is always well developed in 

 my immense material. The shape of the terminal part of the exopod of the uropods differs 

 according to sex, and besides it exhibits some individual variation, so that this part cannot be 

 used as a character in the way applied by Borradaile in his key. Errors in earlier figures 

 as to length of the thoracic legs are also used as characters. Among his five new species 

 based on. the literature only one can be accepted, viz. L. Faxonii Borrad., because it can be 

 recognized, as it is the only species with short eye-stalks inhabiting the Atlantic, at least north 

 of the line. 



Of the 1 2 species established in the whole literature only 3 can be adopted, viz. L. 

 typus M.-Edw., L. Faxonii Borrad., and L. Hanseni Nobili. L. typiis has long and L. Faxonii 

 short eye-stalks, and both were founded on specimens taken in the Atlantic north of the line, 

 where no other form of the genus lives ; L. Hanseni {L. inermis Borr.) can be recognized by 

 Nobili's figure. All the remaining: names in the literature must be cancelled forever either as 

 synonyms or as quite unrecognisable. As already mentioned I have in all 6 species, 3 of which 

 I must name. 



Every adult male can be determined with absolute certainty, as the structure of the 

 petasma affords excellent specific characters. Adult females of two species can always be 

 •determined with certainty, but I have not been able to find any really sharp character between 

 females of the two species with long eye-stalks or between the females of two of the four 

 species with short eye-stalks, viz. L. petiicillifer n. sp. and L. intermeditis n. sp. ; yet it may 

 be added that the majority of the females of the two last-named species can be separated, 

 but some females of the two species are closely similar. More than half-grown but immature 

 specimens can generally be determined, when adult females of the same forms can be separated. 

 The "Siboga" frequently captured specimens of three or four species in the same haul. The 

 analytical keys and the description of the species may elucidate sufficiently the specific 

 characters, differences according to sex and individual variation ; only the male petasma must 

 be described here. 



The petasma is fixed on the inner side of the peduncle of the pleopod (Pis. IV and V, 

 several figures); it projects forwards and obliquely downwards as a somewhat thick plate, and 

 its distal part is obliquely folded strongly inwards and besides directed a little downwards. The 



