SCHIZOPODA. 17 



the spine, at any rate in this species, developes late in life, only after the final adult 

 form is reached. 



The species was taken on the homeward voyage of the ' Discovery,' in the 

 extreme southern part of the Pacific Ocean between New Zealand and Cape Horn. 



Sub-Family Nematoscelin.e, Holt and Tattersall. 



Genus Thysanoessa, Brandt. 



Thysanoessa macrura. 



(PI. HI., Figs. 1-12). 



Thysanoessa macrura, G. 0. Sars, 18H.T ; /,/. (1885); Ortmann, 1893; Stebbing, 1900; Holt and 

 Tattersall, 1900 (1) ; Coutiero, 190G. 



Localities of captures : — 



Winter Quarters. 



No. 4 Hole, 47 specimens, 7-18 mm. 

 No. 8 Hole, 40 „ 8-21 mm. 



No. 12 Hole, 2 „ 7 and 20 mm. 



From River Koettlitz, 2. 1. 03, 6 specimens, 9-14 mm. 

 Outward or Homeward Journey. 



Lat. 61° 46' S., long. 141° 12' E., 16. 11. 01, 18 specimens, 14-20 mm. 

 Lat. 57° 25' 30" S., long. 151° 43' E., 20. 11. 01, 35 specimens, 12-22 mm. 

 Lat. 54° 1' 15" S., long. 170° 49' E., 27. 12. 01, 1 specimen, 6 mm. 

 Lat. 61° 13' 30" S., long. 173° 33' E., 31. 12. 01, 30 specimens, 12-19 mm. 

 Lat. 66° 52' 9" S., long. 178° 8' 15" K, 3. 1. 02, 3 specimens, 8-9 mm. 

 Lat. 70° 29' 27" S., long. 168° 51' 46" E., 26. 2. 04, 1 specimen, 28 mm. 

 Lat. 49° 40' S., long. 172° 18' 30" W., 12. 6. 04, 2 specimens, 8-12 mm. 

 Lat. 58° 49' 45" S., long. 154° 48' W., 24. 6. 04, 4 specimens, 10 mm. 

 Lat. 59° 34' 30" S., long. 106° 28' 12" W., 28. 6. 04, 3 specimens, 7 mm. 

 Lat.'55° 44' S., long. 95° 43' 30" W., 1. 7. 04, 3 specimens, 6-8 mm. 



Form (Fig. 1) of the body rather slender. 



Carapace (Fig. 1) with a single rather long slender spine on the lower lateral 

 margin posterior to the middle, just above the origin of the sixth thoracic limb ; 

 antero-lateral corners acute and somewhat produced ; anterior margins very concave 

 and produced forw^ards inta a long, slender, acute rostrum which reaches beyond the 

 eyes and far beyond the middle of the basal joint of the antennules ; there is a low 

 keel on the anterior part of the carapace behind the rostrum, and a very faint 

 gastro-hepatic groove. 



Pleon (Fig. 1) rather elongate, narrow and attenuate; segments unarmed; sixth 

 segment equal to or slightly less than the combined lengths of the preceding two ; 



