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 MARINE ZOOLOGY on the east shore of the Colne just below the mouth of Blake-stone Hole. This tract is kept constantly wet and soft by water oozing out, and the animals are so abundant that several are often found in each spadeful of material. A number of these have been ex- amined by Mr. A. E. Shipley, and though he cannot identify them with any named species he does not like to give them a new specific name. 2. Priapulus caudatus. This occurs in small numbers at most stations along the coast in mud banks left dry at low water. I have specimens with tails one and a half times as long as the body. Occasionally there are two tails. VII. ARTHROPODA I. COPEPODA A considerable amount of material was collected but had deteriorated too much by long keeping before being properly examined. When the material was fresh I identified the following species with more or less certainty, but probably many others occur in the dis- trict : 1. Dactylopus titboides. 2. Dias longirtmis. 3. Harpacticus c he lifer. 4. Laophontt curticauda, 5. longicaudata. 6. simi/is. J. Psrudocalanus elongatut. 8. Timor a longicornis. II. PANTOPODA (Sea Spiders) 1. Pycnogonum Httorale (StrOm.). An occasional specimen collected at most stations, but it was very abundant in the Crouch at Burnham, living amongst the ten- tacles and on the bodies of the Actinia?, and I think even inside them without apparent in- jury. 2. Nymphon rubrum (Hoda.). A few specimens found in most places, but not so fine or abundant as in the Deben in Suffolk. VIII. MOLLUSCA On the whole I have paid but little atten- tion to the shells, one reason being that they are not of much interest in connection with my special studies, and another being that it seems to me to be a poor district except for a limited number of species, the individuals of which are extremely abundant. I have often been surprised to find so very few species in dredging, and at the great number of dead shells in many places where the living animals arc rare or altogether absent. In some cases this may be due to the extra amount of fresh water at flood time now that the land is better drained, and in others to sewage discharge or to the operations connected with oyster cul- ture. The following list is given mainly to show what are the commonest species, not including those of small size. It might have been made much longer by including dead shells of species which must have lived in the district not many years ago. I mention only those found near the coast alive or very recently dead. The names adopted are those recommended by the Conchological Society. I. AMPHINEURA 1. Craspedochilui onyx (Spengl.). 2. Acantboc hitei fascicularis (Linn.). In the Colne district and probably else- where. II. LAMELLIBRANCHIA 1. Nucula nucleus (Linn.). Dredged off Essex. 2. Mytilui eJu/is, Linn. Common along the coast and largely dredged for manure. 3. Ostrea edulit, Linn. Naturally common, and its culture is the chief industry in some localities. Enormous numbers of dead shells occur where the living animals are seldom, if ever, found, which may have been exposed at the bottom for a very long period ; since, unlike some shells, they decompose very slowly. I often think that many of these dead shells are of more elongated shape than the modern living varieties. These also vary, and those who have paid much attention to the subject can recognize them as coming from particular localities, and how they have been moved from one to another. The large oysters dredged in the North Sea differ greatly from those of the Essex estuaries. The contrast between the comparatively young and well- fed Colchester and Burnham natives, and some of the very old oysters I have occa- sionally dredged from places little, if ever, disturbed is very remarkable. Instead of having large fat animals and thin shells, the animals may be relatively small, and the shell a solid, heavy mass, something like i $ inch in thickness. 8l II