On the Movements and Food of the Herring, etc. 3'91 



face towing nets, which gave great quantities of the beauti- 

 ful little Ctenophore, Beroe cncnmis, Annelid larvae, Zooeae, 

 Amphipods, free swimming larvae of Balamcs, Appendicidaria, 

 many large Medusae (Aurelia aurita), and Diatoms, such as 

 Ooscinodiscus, etc. The temperature of the surface was 50°'5. 

 Later in the afternoon a light breeze sprang up, and the sea 

 surface water was noticed to change, as we sailed slowly- 

 onward, from a beautiful sky blue to a dirty green colour. 

 The towing net showed the latter colour to be due to a great 

 quantity of argillaceous matter in the water, probably flowing 

 from the river Tay. Very little animal life was found. 



The afternoon of the 23d was spent in trying to beat round 

 Peterhead, but this was not accomplished, owing to the wind 

 dropping to a dead calm. Taking advantage of this, I was 

 enabled to work the towing nets, and obtained the following 

 animals : — Thysanopoda, Amphipods, Zoceae, Copepods, Balamis 

 larvae, Appendictdaria, Peridinium, Beroe, and a few Diatoms. 

 At 9 P.M. a fresh breeze sprang up from the south-west, 

 and this being a favourable wind for us, w^e were able to 

 make good progress passing Peterhead. At 10 p.m., with the 

 barometer falling steadily, a great deal of phosphorescence 

 w^as noticed on the surface of the water, which, on examina- 

 tion, was found to be caused greatly by the Nyctiphanes 

 {Thysanopoda) norvegica, M. Sars, and Zoceae. 



At 9 A.M. on the 24th we were 30 miles north-east by 

 north off Kinnairds Head, when another complete change in 

 the colour of the sea was observed from a light blue to a 

 milky or slate green. Several buckets of water were drawn, 

 and some taken with a large glass jar, all of which was 

 exceptionally clear. The tow-nets were w^orked for half-an- 

 hour in this locality, and with the exception of one or two 

 Copepods, no pelagic animals were present. It took the 

 "Energy" — going fully 5 miles an hour — about three-quarters 

 of an hour to pass through this belt of peculiar coloured 

 water before emerging again into the ordinary blue sea. 

 During this time the temperature of the surface was taken at 

 intervals of 15 minutes, and read as follows: — 51°'5, 51°"8, 

 and 51°"9. At 4 p.m. the surface temperature had fallen to 

 49°, and this seemed to me a very remarkable coincidence. 



