88 MEMOIRS OF THE CARNEGIE MUSEUM 



Several specimens off the southern coasts of Kiusiu and Hondo, taken in 

 the intermediate nets operated at 300 fathoms and below. The largest indi- 

 vidual is 45 mm. long, but answers well to the description and figure of the 

 type, though this was very immature (17 mm. long). The photophores and 

 the pre-orbital luminous organs do not vary in size or position with growth. 

 The first antero-anal is not equally elevated with the second supra-anal as shown 

 in the figure, but is constantly below the level of the latter. The lower pre- 

 orbital varies extensively in different specimens, as in the closely related D. 

 theta, being sometimes reduced to a small spot below the anterior margin of the 

 pupil and sometimes developed so as to fill in the entire space between the 

 eye, the front of the premaxillaries, and the nostril. A suborbital dot is usually 

 present below the middle of the pupil. The anal photophores are usually 

 5 -H 4 or 5 + 5 in number, occasionally 6 + 4 or 6 + 5, 3 in the posterior group 

 on one side only in one specimen. In a few individuals, including several very 

 immature and one of larger size, the first antero-anal is not elevated, but lies 

 close to the base of the anterior anal rays. In all other respects, including the 

 angulated supra-anals and the high position of the upper row of photophores, 

 these agree with the other specimens, so we are clearly concerned with a 

 question of individual variation. 



List of Stations. 

 4920. 30° 34' N., 129° 22' E Intermediate net, 300 fathoms. 



4951. 31° 10' 30" N., 131° 58' 30" E. Intermediate net, 300 fathoms. 

 4954. 32° 05' N., 133° 02' E. Intermediate net, 300 fathoms. 



5063. 35° 01' 10" N., 138° 38' 50" E. Intermediate net, 300 fathoms. 



17. Diaphus tanakae sp. nov. 



Type 21 mm. long, from Albatross Station 4951, off the southern coast of 

 Kiusiu (31° 10' 30" N., 131° 58' 30" E.), intermediate net at 300 fathoms. 



Very closely related to D. nanus Gilbert, but with the upper series of 

 photophores somewhat higher, the third supra-anal vertically above the second 

 or slightly in advance of it (well behind it in D. nanus), the posterolateral 

 vertically above the last antero-anal (behind it in D. nanus) , and the last pre- 

 caudal interspace decidedly wider than those which precede (but little wider in 

 D, nanus). The eye is smaller, the snout longer, the maxillary much longer, 

 the pre-orbital luminous bodies are different in shape and in extent. 



Measurements in hundredths of length without caudal (16 mm.): Length 



