FISHES OF THE GULF OF MAINE 151 



General range and occurrence in the Gulf of Maine. — This species is undoubtedly 

 oceanic and only a stray within the limits of the Gulf, but one specimen has been 

 found in the stomach of a cod caught on Browns Bank.°^ 



FAMILY STOMIATID^«» 



This family includes a large number of soft-rayed oceanic fishes of the mid-depths 

 and of the most diverse appearance, all of them with well developed phosphores- 

 cent organs, very large eyes, large mouths, a lower jaw projecting beyond the upper, 

 and with teeth in both jaws. Some have and others lack the adipose fins, but in all 

 of them the ventrals are inserted far back on the abdomen. They differ from the 

 herrings and salmons in the structure of the skull. Only one species, the pearlsides 

 (p. 151), has been recorded more than once or is to be expected except as a stray 

 in the Gulf of Maine, but two others have been taken there casually. 



53. Pearlsides {Maurolicus pennanti Walbaum) 

 Pearlfish; Lanternfish 

 Jordan and Evermann, 1896-1900, p. 526. 



Description. — The presence of an adipose fin between dorsal and caudal, 

 togetherwith phosphorescent organs, distinguishes the pearlsides (fig. 61, p. 150) from 

 all other fish that occur regularly in the Gulf of Maine. This is a flat-sided, large- 

 headed little fish, its body (about one-fifth as deep as long, excluding caudal fLn) 

 deepest forward of the ventral and dorsal fins, its eye very large, its lower jaw pro- 

 jecting, its mouth large but oblique, and both its jaws armed with minute teeth. 

 The dorsal fin (about 11 or 12 rays) stands above the space between ventrals and 

 the anal, which is longer than the dorsal. The adipose fin (both of Woods Hole '" 

 and of Noi-wegian^' examples) is low and long, much as in the capelin." The 

 caudal fin is broad and slightly forked. 



The pearlsides has been described as scaleless, but this is not correct, for both 

 Scandinavian and Woods Hole specimens have been found to be clothed with large 

 but extremely thin transparent scales. There is no definite lateral line. 



The most interesting and diagnostic feature of the pearlsides is the 

 presence of a series of phosphorescent organs or luminous dots situated as follows: 

 First, 12 pau's along the belly between pectoral and ventral fins, followed by 5 or 6 

 from ventral to anal, and, after a gap, by 24 or 25 between the center of the anal fin 

 and the base of the caudal fin, all these together forming a practically continuous 

 row on each side of the belly from tliroat to tail. Second, a row of larger spots 

 shghtly higher up on each side, 6 from chin to pectoral fin, 9 thence backward to 

 the ventrals. Third, a group of 6 low down on each side of the cheek and throat; 

 likewise a spot in front of the base of the pectoral and 2 on the chin.''' 



•' Reported by Goode and Bean (1896). 



** We follow Boulenger in including the pearlsides, viperfish, and cyclothone in this one family. 



'• Sumner, Osburn, and Cole, 1913, p. 743. 



" Smitt, Scandinavian Fishes, 1892, p. 933, pi. 44, fig. 3. 



" Goode and Bean (1896, p. 96) describe it as "very small," but probably their specimens were battered. 



" This account is based chiefly on Smitt's description and plate. 



