PELAGIC ANIMAL LIFE 



60- 



The families Stomiatidae and Sternoptychidae present many points of 

 resemblance, and comprise many fishes which were previously looked 

 upon as genuine deep-sea forms. They vary greatly in shape, some 

 being long and slender, others short and laterally compressed, and the 



Fio. 453- 



Sfomias boa, Risso. Nat. size, 16 cm. 



mouth is large with a great number of teeth. Both families are 

 characterised by abundant light-organs, the only difference between 

 them lying in the fact that the Sternoptychidae have only one kind of 



Fig. 454. 

 ChauUodus sloanej , Bl. and Schn. Nat. size, 6 cm. 



light - organ, while the Stomiatidae have below or behind the ^eye 

 large and powerful light-organs, very often coloured, quite different in 

 structure from the small ones on the bodv. 



Fig. 455. 

 Photostotnias guernei , Coll. Nat. size, 17 cm. 



The Stomiatidae occurring most commonly in the Atlantic are 

 Stoniias boa (see Fig. 453) and ChauUodus sloanei (see Fig. 454), both 

 taken in the tow-nets of the " Michael Sars " at nearly all oceanic 

 stations. They both occur in all oceans, and some of the rarer forms, 

 like Macros toiiiias longibarbatus, Malacostetis indicus, and Astronesthes 

 niger, are also known from other oceans. An interesting species. 



