MARINE SILVER HATCHETFISHES — SCHULTZ 591 



Table 1. — Counts of vertebrae recorded for the Slernoptychidae. 



Genera, species, and 

 subspecies 



Number of Vertebrae 



28 29 30 31 32 33 34 35 36 37 38 39 40 



Argyropelecus 



afjinis 



pacific us 



gigas 



hemigymnus 



intermedins 



amahilis 



aculeatus 



olfersi 



lynchus 



lynchus 

 sladeni 

 hawaiensis 

 Slcmoptyx 



diaphana 

 Polyipnus 



polli 



laternatus 



In phanos 



asteroides 



matsubarai 



fraseri 



unispinus 



nuttingi 



indicus 



tridentifer 

 Western 



Australia 

 Philippines 



spinosxis 



spinosus 

 slereope 



2 3 

 5 3 



3 — 



1 

 12 



5 J i 



15 



:; 



l 



1 11 



3 1 — — 

 — — 3 — — 



— 13 12 1 — 

 24 3 — 



9 — 



— — — 2 3 6 — 



— — — — 4 40 2 



— —181 — 



Key to the Genera of Sternoptychidae 



la. Abdominal photophores 12 and supra-abdominal 6; suprapectoral photo- 

 phores 2; no supra-anal or lateral photophores, see figure 1, p. 588. Dorsal 

 blade present and well developed in front of dorsal fin; on maxillary the 

 anterior teeth point posteriorly, and posteriorly located ones point ante- 

 riorly Argyropelecus Cocco 



lb. Abdominal photophores 10 and supra-abdimonal none to 3; suprapectoral 

 photophores 3, dorsal blade present but very small and scarcely evident 

 externally; none of the maxillary teeth point forward. 

 2a. Dorsal blade present represented externally by a long spine; photophores 

 as follows: anal 3; branchiostegal 3; isthmus 5; preanal '.'<; supra-ab- 

 dominal none; supra-anal 1; lateral none . . . Sternoptyx Hermann 

 2b. Dorsal blade evident externally as a short, low paired keel just in front 

 of dorsal fin; photophores as follows: anal 4 to 15; branchiostegal G; 

 isthmus 6; preanal 5; supra-abdominal 3; supra-anal none to 3; lateral 1. 



Polyipnus Giinther 



