FISHERY BULLETIN: VOL. 69. NO. I 



at night. Unfortunately, the micronekton net 

 was not used on Rockaway (12.000 series), and 

 insufficient numbers of older stages (metamor- 

 phosing specimens and juveniles) were taken in 

 plankton hauls to permit a meaningful separa- 

 tion of the two species in waters to the south 

 of lat 5° S in this series. 



Vinciguerria poweriae (Cocco) co-occurred 

 with V. nimbaria in the central water mass of 

 the North Pacific (Ahlstrom and Counts, 1958), 

 but no material of V. poweriae was obtained in 

 EASTROPAC collections. However, material 

 of V. attenuata (Cocco) was obtained from 

 farther south in the eastern Pacific on the 

 "Downwind Expedition" — hence all four spe- 

 cies of Vinciguerria do occur in the eastern 

 Pacific. 



Other gonostomatids (42 occurrences, 88 larvae) 



Included in this category are larvae of two 

 identified genera, Gonostoma and Woodsia, and 

 several kinds of larvae that are unmistakably 

 gonostomatid, but not identified as to kind. 



6. STERNOPTYCHIDAE 

 (337 occurrences, 5,687 larvae) 



Hatchetfish larvae ranked third in abundance 

 (5.98 /f of total), exceeded by larvae of Mycto- 

 phidae and Gonostomatidae. The majority of 

 hatchetfish larvae were those of Sternoptyx di- 

 aphana Hermann, and most of the remainder of 

 Argyropelecus lychmis Carman. Because larvae 

 of Sternoptychidae are more fragile than most 

 other kinds and are usually in poor condition, no 

 attempt was made to identify them to genus or 



species. Areal occurrence and relative abun- 

 dance of sternoptychid larvae on EASTROPAC 

 I are summarized in Table 12. Larvae were not 

 only taken in markedly more collections between 

 lat 10° N and 10° S— 94 9^ of the collections 

 were positive as compared with only 41 % in 

 the remainder of the pattern — but more larvae 

 were taken per positive haul — 21.1 larvae as 

 compared with 5.2. 



7. ASTRONESTHIDAE 

 (12 occurrences, 13 larvae) 



Several kinds of astronesthid larvae were 

 collected in the EASTROPAC area: only one 

 kind had heavy pigmentation on the body; the 

 others were lightly, but characteristically pig- 

 mented. Larvae of Astronesthidae are similar 

 in appearance to other stomiatoid larvae; they 

 have a slender, elongated body, and a long in- 

 testine that underlies the body for about Yiq or 

 more of the standard length, and usually has 

 a free terminal, trailing portion that can be quite 

 long, often trailing beyond the caudal fin. As- 

 tronesthid larvae can be distinguished readily 

 from other stomiatoid larvae by the forward po- 

 sition of the dorsal fin in relation to the anal 

 fin. Developmental series of astronesthid larvae 

 have not been described in literature. Eleven 

 of the 12 occurrences of astronesthid larvae were 

 taken within 10° ± of the equator. 



8. CHAULIODONTIDAE 

 (80 occurrences, 165 larvae j 



Larvae of Chaidiodus are readily identifiable 

 to genus, but are difficult to separate at the spe- 



Table 12. — Areal occurrence and relative abundance of larvae of Sternoptychidae on EASTROPAC I. 



20 



