22 



OSCAR SUND 



[REP. OF THE "MICHAEL SARS" NORTH 



S. vigilax is probably limited to the tropical At- 

 lantic : ). It was taken only on the southern section, from 

 Africa to the Sargasso Sea. The catches were too few to 

 allow any definite conclusions regarding the bathymetrical 

 distribution to be drawn, but the table seems to indicate 

 that (1) the adults prefer deeper water than the young, 

 (2) that the adults sink during the night. 



Fig. 35— 38 Sergestes vigilax, 35) ? 7, st. 67, y 1200, rostrum (*%). 



36) d" 6, st. 29, y 400, end of 3. mxp. ( 2 %). 37) <? 6, st. 29 y 400, 



outer uropod ( 10 /i). 38) d" 6, st. 29, y 400, petasma ( 3 %). 



l ) Hansen's opinion (1896) that Bates' S. parvidens, which was 

 taken both in the Atlantic and the Pacific, is the young of S. vigiiax 

 is certainly wrong. The eyestalks are, as represented by Bate, much 

 too short. In a specimen of 5. vigilax of the same size they are 

 much more than half the length of the carapace. It is equally cer- 

 tain that 5. macrophthalmus, Stimps. is not the mastigopus of 5. 

 vigilax. The "Michael Sars" specimens of young S. vigilax agree 

 fairly well with Stimpson's description, but they seem to have more 

 numerous dorsal spines, which are found not only, as in 5. macroph- 

 thalmus, on the hinder edge of the carapace and on the fourth and 

 fifth abdominal joint, but also on the third and sixth joints up to a 

 size of 7—8 mm. (C = 2,5 mm.). The size given by Stimpson (0,7 

 inch = 17 mm.) suggests that S. macrophthalmus is uot identical 

 with S. vigilax, as this species has lost all its dorsal spines before 

 it attains a total length of about 13 mm. 





Number 



Size 







P3 



Depth 

 (metres) 



of hauls 



< 4-9 



> 4-9 









D 



N 



D 



N 



D 



N 



D 



N 



o 



0—50 



5 



5 



43 



64 



4 



14 



47 



78 



125 



100—200 



4 



9 



8 



6 



2 



21 



10 



27 



37 



300— 



5 



6 



5 



3 



11 



6 



16 



9 



25 



Total 



14 



22 



56 



73 



17 



41 



73 



114 



187 



Gr. total.... 



36 2 ) 



129 



58 



187 





Table of catches. 



St. Gear m. w. Number 



23 



20 



42 

 45 



47 

 49 



51 



52 



53 



58 



62 



64 



67 



y 



T 



y 



y 



1 sn 



y 



y 



V2 sn 



y 



4 In 



y 



1 sn 



y 

 y 

 y 



4 In 

 1 sn 



V2 sn 

 3 In 



1 sn 

 1 sn 



1 sn 

 1 sn 



y 

 y 



1 sn 



y 



1 sn 

 1 sn 

 1 sn 



y 



3 U sn 



y 

 y 



1 sn 



y 

 y 



400 



(1215 m) 



400 



300 



100 



300 



2000 



40 



370 



1000-0 



2000 







300 



2000 



3000 



4000 







100 



1200 







60 



100 



200 



300 



600 



100 



300 



200 



100 



200 



300 



600 



1000 



2000 



50 



200 



1200 



1 

 1 

 3 

 1 

 15 



6 

 1 

 4 

 6 

 1 

 2 

 27 



2 

 1 

 2 

 1 



22 



3 



2 



1 



22 



11 



5 

 5 

 1 

 1 

 1 

 1 

 12 

 2 

 3 

 1 

 8 

 1 

 6 

 2 

 4 



Sex, size 



?7 



?7 



d" 7, 5.5, ? 4.5 



c?7 



d" 7, ? 6, 5, 5, © 4, 4, 4, 3.5, 3.5, 3, 3„ 



2, 2, 2, 2 

 2 7, 7, 6, cj» 6, 6, 6 

 d"6 



© 3, 3, 3, 3 

 ©5, 3, 2.3, 2.2, 2.2, 2.0 

 c?7 



© 2.6, 2 

 2 7, © 6 a 1.5, 5 a 2, 9 a 2.5, 2 a 3, 3 a 



3.5, 1 a 4 mm. 

 2 6, 6 (def.) 

 26 



2 6, © 3.5 

 26 

 2 6, 5, 01a 3.5, 1 a 3, 6 a 2.5, 6 a 2, 



5 a 1.5, 1 a 1 mm. 

 2 5, 5, © 4 

 2 6, d"6 

 ©4 

 © 2 a 4.5, 2 a 4, 5 a 3.5, 5 a 3, 6 a 2:s y 



2 a 2 mm. 

 2 7, 6, 6, 6, 6, 6, 5-, 5, © 4.5, 4.5, 4. 

 2 8, d" 6, 6, 6, 6 

 2 7, 7, 6, 6, 5 

 26 

 c?6 

 27 

 d"7 



© 4 a 4.5, 1 a 4, 3 a 3.5, 1 a 3, 3 a 2.5 

 ©2,5, 2.3 



©3.0, 2.8, 1.5 

 ©2.6 



2 6, d" 6, 5, 5 © 4.5, 4.5, 4, 3 

 26 



©3.2, 2.8, 2.7, 2.3, 2.2, 1.7 



©3, 2 



2 7.5 (L = 24) 6, 5, 5 



! ) One vertical haul (one specimen) not considered. 



