A DAY ON THE CROUCH RIVER. I47 



thorouglily withdrawn themselves with a snap into the shell, it is 

 quite impossible to extract them by force, but a gentle tapping on 

 the apex of the \Vhelk-shell with the cull-tack or a knife blade will 

 soon cause them to tumble out. When put in a bucket with two or 

 three empty shells, it is interesting to note how speedily they provide 

 themselves with a new house. There are other, but less humane, 

 methods of dislodging the Pagurus from its home. 



A fine Lobster had been taken in the river the day before our 

 visit, but such grand Crustaceans did not fall to our luck. 



A large Rhizostoma brought up in the trawl was put into a bucket 

 of clear water, and this was soon filled by dozens of the very active 

 Hyperea latreillii, shooting about in all directions near the top of the 

 water. Their large, elongate, bright apple-green eyes were especially 

 noticeable. These little Crustacea were parasitic within the pellucid 

 gelatinous substance of the Medusa, especially between the peduncle 

 and the umbrella-like disk. I also found its tick-like larva (figured 

 in Gosse's "Naturalist's Rambles on the Devonshire Coast," pi. xxii. 

 fig. 15). Those I brought home were much larger than his grain of- 

 sand-sized specimens. 



Many Shrimps and Sandhoppers, or " Skipjacks,'' were captured, 

 but I am not sufficiently acquainted with them to attempt to give a 

 list of the species. Idotea emargitiata was in the greatest abundance, 

 and we took several Crangon vulgaris (Common Shrimp) alive. 

 Oysters, mussel-shells and stones were covered with the Acorn Bar- 

 nacle {Balanus porcatus) locally known as " chitters." 



Of the Actinaria or Sea-anemones we only found two spe- 

 cies. The Beadlet {Actinia mesembryanthemum) was abundant, 

 but all of the liver-brown variety. In one of the bottles you will see 

 three Daisies {Sagartia bellis). 



The day was not hot enough for us to see many of the common 

 jelly-fish {Aurelia aurita), near the surface of the water, as was the 

 case in the Blackwater on September 15th, 1888, (Essex Nat. ii. 247), 

 when 



" Thick as blanc-mange the jelly-fish clung to the sluggish keel." 



Many, however, were noticed, and on one or two hauls the trawl 

 was so filled with " blubber " that care had to be exercised to avoid 

 breaking the net, and when the cord was untied the deck was covered 

 with the jelly-like substance. A few of these common jelly-fish were 

 pale purple in colour, far the larger majority being white, but none 



