296 



At 



25 



50 



75 



100 



DR. G. H. rOWLEE — BISCATAJST PLANKTON : 



25 per cent, of 8 hauls by day, with 0'8 



fathoms 

 this species 

 occurred in 



It would seem possible that the plurimum at 75 fathoms by day rose to 50 fathoms at 



night. 



AucHicoNCHCECiA cucuLLATA, Brady. 

 This species occurred in the following hauls: — 32 Z (JiOO-300 fathoms), 34 e (750- 



500 fathoms), 27 b (1250-1000 fathoms), 27 a' (1250-0 fathoms). 

 member of the deeper mesoplankton. 



It was obviously a 



CYPRIDINID^. 



Cypridina castanea, Brady. 



This species occurred in the following hauls : — 32 m (75 fathoms), 32^ (100 fathoms), 

 36 <7 (200-0 fathoms), and S6h (250-0 fathoms). It is worth noting that the two 

 epiplanktonic captures were between 10.30 p.m. and 1.30 a.m. 



GlGANTOCTPMS PELLUCIDA, Miiller. 



The two captures of this species give the first definitive evidence that it is a 

 deep-water form, previous captures having been made with open vertical nets. Both 

 are very deep : 31 d at 1000-750 fathoms, and 26 b at 2000-1500 fathoms. 



The Vertical Distribution op the Ostracoda as a whole. 



The first point to be considered is the general distribution of the planktonic Ostracoda 

 (practically that of the Halocypridse) during the period and through the area in- 

 vestigated. This can best be grasped by taking the comparable hauls at each depth, 

 and the average specimens per hour or per 100 fathoms which they yielded. To the 

 specimens recorded in the General List (pp. 312-313) have been added all specimens 

 which were too much broken for identification, a few indeterminable larvre, and the 

 seven species which occurred so rarely as not to have been printed in the general list. 



