592 BULLETIN OF THE UNITED STATES EISH COMMISSION. 



a line parallel with base of anal fin, the seventh elevated, un a line juining sixth with posterolateral; 

 6 posterior anals. The distinguishing features are especially the elevated second ventral, the presence 

 of but 2 (instead of 3) sujira-anals, and the very high position of the uppermost series. 



The differentiation i >f the upper half of each photophore and its sui)erlidal separation from the Ic iwer 

 half by a pigment band can lie made out only when the photophores are uninjured and are still pro- 

 tected by the scales. It is possible that all species heretofore grouped in CitUeitia and A'A)ii>in-i>m j)os- 

 sess the character of divided jihotophore. In this case we should range them under the oldest name, 

 Dittjiliiix, as we do not consider tlie presence or the extent of the preocular photophore of generic 

 imj)ortance. If the current system of minute subdivision be followed to its logical extreme, D. 

 uriditnipuK mu-st be considered the type of a new genus, distinguished ))y the absence of preocular 

 photophores, and D. cliri/sorliynclius the type of another characteiizeil by the large preocular plujto- 

 phore, which covers the entire snout (as in .Etho/jroru). 



Biaphus urolampus Gilbert tt Cramer, Proe. U. s. Nat. Mus.. .\i.\, 1897. p. t(W, pi. ;]s, lig. 1. 

 Diaphiis chrysorhynchus 'iilbert & Cramer. 



Four specimens were taken at the following stations: No. o.s.'U, nii Kaunukakai, Mulcikai, .-surface; 

 3921, off Honolulu, surface; 4117, off northwest coast Oahu, 253 to 2.S2 fathoms. 



The specimen from station 4117 came to haml in perfect condition and must have entered the 

 trawl near the surface. All otlier specimens known, in<:luding ty|>e antl cotypes, were obtained in 

 the surface tow net. 



The bluntly munded snout, covered by the preocular photo|]hiirc, gives a strong resemblance to the 

 specie.s of .Etliojironi, which differ only in their .simple photophores. It is not improbable that 

 ]ierfect specimens of .Ktho/ironi and Collcttia, witli scales still in jilace, will show their photophores 

 also to lie divi<led by a black pigment line, in udiich ease the species may be united under the oldest 

 name, Diaplntn. Xi/cIojjIikx, Cocco, used by Brauer for this grouj), was proposed solely as an amended 

 form of Mi/rlijjiliuin, and is therefore not available. 



The photophores of I). i-liri/fsorlii/ncJtus show thc> following characteristic arrangement: Two lower 

 pectorals on each side forming diverging lines e.vtendiug from first thoracics to middle of pectoral base, 

 third pectorals high on sides, nearer lateral line than jiectoral fins; fourth thoracics elevated, on a level 

 with ventral liase, vertically over the third thoracics; five ventrals, the first, second, and third pairs 

 forming oblique diverging lines, the third a little above level of ventral base; supra-anals 3, forming a 

 nearly vertical line from vent, the uppermost more widely spaced, and in contact with the lateral line; 

 the first anal (interpreted as supra-anal in descri])tion cited below) elevated, in a line joining second 

 anal and upper supra-anal; second to fifth anals in a straight or gentlj' curved line, the .sixth strongly 

 diverging, in a line which includes the posterolateral; the posterolateral in I'ontact with the lateral line; 

 five anals in the posterior series. 



In the arrangement (jf its iihotophores this species agrees very closely with D. Ihela Eigenniann it 

 Eigenmann and IK ndriKiiiius, ]mi lluin has the ujiiier lateral sjints much less elevated and the lirst 

 anal on a level with the others, while <iili'ii(tiiifix has tlu' upper peitoral much less elevated, and those 

 of the anterior anal group describe a wide curve. J), i-liriinorliiiiii-hiix shows no variation in the number 

 or arrangement of its photophores (except that in one specimen there are on one side (i in,«tcad of 5 

 po.sterior anals) nor in the size of its preocular luminous area. 



Diaphus rhrysorlnjiirhiis CiUterl & Cramer, Troc. U. S. Nat. Mns., xix, 1.H97. i09, pi. 3,H, lig. 3 (unt fig. 2, as erniliecjusly 

 inrlientcfl rm the plate and in [he description). 



Diaphus adenomus, new species. Plate 68. 



Type, a female with developed spawn, 10 cm. long, from Albatross station 4106, the Kaiwi Channel 

 between Oahu and Molokai, depth 335 to 350 fathoms; type. No. 5158S, U. S.Nat. Mus. 



Head 28 hundredths of total length, excluding caudal; greatest depth of body 23; least depth of 

 caudal peduncle 10; distance from last anal ray t(j lirst caudal ray 18, length of pectoral 10; length of 

 inner ventral rays 17; Ijase of anal 19; ba^e of dorsal 21; diameter of eye 6; width of middle of iiiter- 

 orbital space 8.5; length of snout 4.5; length of maxillary 20.5. D. 15; A. 15; P. 12; V. 9; si'ales in 

 lateral line 36. 



