7 2 



Sagitta pulchra Doncaster. 



Localities: 



Malay (Siboga area) and Maldive Archipelagos. 

 Definitive observations: 



Neritic. 

 Surface. 

 Temperature: 28 to 29 C. 



Sagitta regularis Aida. 



Localities: 



Malay (Siboga area) and Maldive Archipelagos; Japan. 

 Definitive observations: 



Neritic. 



Surface. 



Temperature: 28 to 29 , and M.A. 2i°C. 



Sagitta robusta Doncaster. 



Localities: 



Malay (Siboga area) and Maldive Archipelagos. 

 Definitive observations: 



Neritic. 



Surface. 



Temperature : 28 to 29 C. 



Sagitta serratodentata Krohn. (Charts IV to VI). 



Localities: 



Temperate (N. and S.) and tropical Atlantic; and Mediterranean, Southern Ocean, Tropical 

 Indo-Australian Ocean, and Japan. 



Definitive observations: 

 Neritic and Oceanic. 

 N. limit: 6o°i2'N., 22°s6'W. 

 S. limit: 53 o' S., 70°4o' W. 

 Surface and Mesoplankton. 

 Deepest haul: 364 to 182 m. at ii°5C. 

 Highest temperature: 32 C. 

 Lowest temperature: M.A. 6°sC. 



In spite of the wide range of temperature, and the wide horizontal distribution, there is 

 at present a marked northern limit to this very characteristic species at about 6o° N. It has so 

 far failed entirely in the north-eastern arctic arm of the Atlantic, although collections from that 

 region have been (comparatively speaking) numerous. 



It is curious that while the records show it to be markedly eurythermal, they do not 

 point to its being correspondingly eurybathic; the deepest record is shallow for a species which 

 can tolerate the temperature of the Falkland Islands and Straits of Magellan. 



