FISHERY BULLETIN: VOL. 70, NO. 3 



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Figure 13. — Developmental stage of Taaningichthys minimus Taning. — A, 7.3-mm larva, Hawaii Institute of Ma- 

 rine Biology, China Hat Series 3; B, 7.3-mm larva, dorsal view; C, 14.4-nim larva, SIO-FCRG Cruise 71-2. 



are innervated by medial rami of spinal nerves; 

 however, the first two of these each receive a 

 small ramulus from a ventral spinal ramus. Ray 

 believed that the innervation of lateral body 

 photophores by ventral components of spinal 

 nerves supported Bolin's (1939, p. 131-132) sug- 

 gestion that lateral body photophores were de- 

 rived by upward displacement of certain photo- 

 phores from a single pair of ventral photophore 

 rows. In lanternfish, such as T. mexicanus, 

 Bolinichthys, and Notolychnus, the photophores 

 which lie above the lateral line have always been 

 considered homologous to their counterparts that 

 lie below the line in other genera. Our finding 



of a cranial nerve supply for photophores above 

 the lateral line in T. mexicanus, Bolinichthys sp., 

 and Notolychnus casts considerable doubt on the 

 theory that these photophores could have arisen 

 from upward displacement, "from a primitively 

 ventral and strictly linear series" (Bolin, 1939, 

 jx 131-132) or even from "two ventrally located, 

 parallel series of photophores, such as we find 

 in Vinciguerria" (Bolin, 1939, p. 97). 



An alternative hypothesis for the evolution of 

 photophore patterns became apparent to us 

 when studying the transforming stages of Scop- 

 elo])sis (Figures 2, 3) . It is obvious that in these 

 specimens, the so-called primary photophores 



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