the anal photophores approaches that in the recent species Myctophum 

 anderssoni Lonnberg; in this form, the supraanal (SAO) organs are 

 lacking (Norman, 1930), while out of the 14 — 15 anal (AO) photophores 

 the first two occur higher up than the rest. Eomyctophum Danil. 

 displays certain differences in this respect, since there are only 10 — 13 

 anal organs (AO), of which the first 2 — 3 are elevated. 



Of the remaining precaudal photophores, 4 — 5 ventral organs (VO) 

 may be noted in some specimens, placed in a single row between the 

 base of the ventral fins and the beginning of the anal fin. Moreover, 

 on some specimens 1 — 3 traces of photophores of the thoracic row (PO) 

 are to be observed immediately behind the head, and the margin of 

 the abdomen. 



In the precaudal area of some individuals, we may observe, in 

 addition to the photophores here described, a number of similar black 

 spots. They occur either all over the body, or dorsally only, as well as 

 on the gill covers (Fig. 7). It is supposed that their presence on the 

 head is confined to places covered with scales. Two possible interpre- 

 tations of these black stains may be advanced: 



(1) analogously as in the living species of the Myctophidae 

 (Lampanyctus longipes and L. alatum; Brauer 1906) they might be 

 minute luminous organs, or , 



(2) they might merely be the traces of some shght pigmentation 

 not associated with the presence of photophores. A clarification of the 

 origin of these tin;y stains calls for the discovery of better pre- 

 served photophores in forms not destitute of scales. Such photopho- 

 res should, moreover, be represented not merely by a pigment cup but 

 by complete glands as in the Miocene species of the genus Myctophum 

 (Arambourg, 1921, 1925) or in the Oligocene species of the genus Diaphus 

 (Kalabis 1948). 



Another interesting occurrence of pigment is its accumulation as 

 a narrow dorsal band, close to the base of the caudal fin (Fig. 9). By 

 analogy with the recent forms, it might in turn be supposed that we 

 are dealing here with pigment remains such as are encountered in the 

 same place on the luminous plate in representatives of the recent 

 species of the genera Myctophum and Lampadena. In Myctophum, this 

 plate is also a secondary sexual characteristic, since it is confined to in- 

 dividuals more than 2 cm long, always ventrally in females and dorsally 

 in males (Brauer 1906). Such a band of pigment is present on many 

 of the- writer's specimens, but always on the dorsal side. 



To conclude the description of the arrangement of luminous organs 

 in our material, it should be mentioned that the presence below the 

 lower jaw of 3 large branchial photophores has been observed by the 



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