THE OSTEACODA. 



295 



CONCHCECIA TYLODA, MiiUer. 



One unmistakeable specimen occurred in 24 a (1250-1000 fathoms) ; and a pair of 

 empty shells which seemed also attributable to this species was found in 30 «' (1500- 

 1250 fathoms). 



CONCHCECIA ZETESIOS, Sp. n. 



The specimens were so few that they are better not expressed in the usual averages. 

 A pkirimum (if the word can be used of so small a number) was, however, noticeable at 

 100 fathoms. The species would seem to have inhabited the lower epiplankton and 

 upper mesoplankton. Only three specimens were taken by night. 



At 



50 



75 



100 



Between 200-100 

 300-200 



fathoms 

 this species 

 occurred in 



i 



'' 2 out of 13 hauls, with 4 specimens *. 



2 „ 10 „ 2 „ 



3 „ 17 „ 11 



7 

 3 



HAIiOCTPRIS GLOBOSA, ClaUS. 



The following table shows the distribution of this species in the epiplankton ; it has 

 clearly a centre in the lower epiplankton, the specimens were thickest at 50 fathoms, 

 the occurrences most numerous at 50, 75, and 100 fathoms : — 



At 



15 per cent, of 13 hauls, with 05 

 58 „ 12 „ 2-2 



84. „ 13 „ 14-9 



80 „ 10 „ 9-7 



88 ,, 17 ,, 3"6 V 



average 



specimens 



per hour haul. 



Below 100 fathoms only one specimen was captured, the single male at 750- 

 600 fathoms. 



This is remarkable because the species was common in the epiplankton, and many 

 specimens must die, yet not a single one appeared in the closing-nets. This fact 

 suggests that a comparatively large form (84 per cent, of the specimens were over 

 2 mm. in length), when dead and sinking, is more likely to be snapped up for food 

 in the dark, than a tiny form such as curia or rotundata ; this seems reasonable, 

 because tliei-e is more of it to be touched or smelt. 



* Actual numbers ; uot multiplied by a time-fuctor. 



