158 DARK UNFATHOMED CAVES OF OCEAN 



young : in each ovary only the eggs of the layer 

 that lies immediately beneath the ovarian envelopes 

 give rise to embryos, and it seems as if all the rest 

 of the roe were used up as food by the unborn 

 fry. There is nothing improbable in this suggestion, 

 for it is well known that in the Embiotocidcs, a 

 small family of viviparous bony fishes that inhabit 

 the coasts of the North Pacific, the developing young 

 are in part nourished by the epithelium of the wall 

 of the mother's ovary. 



The Crustacea of this haul included a number of 

 specimens of a new kind of prawn, Psathyrocaris 

 fragilisy remarkable for the enormous length of the 

 exopodites of the last four pairs of thoracic, and first 

 five pairs of abdominal legs : so long are these 

 exopodites that the creature at first sight looks more 

 like an Opossum-shrimp than a prawn. 



I left the Investigator at Bimlipatam, in order that 

 I might myself take to the Museum at Calcutta the 

 many boxes of specimens collected at the Coco 

 Islands, and in our phenomenally successful deep-sea 

 dredgings on the passage there and back. I felt as 

 if I were unfaithful to my ship in leaving her in the 

 middle of a surveying season ; but at that time so 

 little progress had been made in arranging and inter- 

 preting her collections that I began to think that I 

 should serve her best by making an effort to work 

 up some of her arrears rather than by making 



