Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.703633
Title: 21 published articles on zoology
Author: Atkins, D.
Awarding Body: University of London
Current Institution: Royal Holloway, University of London
Date of Award: 1939
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Abstract:
While investigating the moulting stages of pea-crabs, a nocturnal colour change— analogous to that described by Gamble and Feeble in Fippolyte (Quart. Journ. Micros. S c i., 1900; Phil. Trans. Roy. Soc.,E, 1903,1905) - was observed by me in what is apparently Pinnotheres veterum. Last June I received from the Marine Biological Association, Plymouth, an ascidian (A.mentula) which had been dredged off the Mews tone, and from the branchial chamber of which a pea-crab had been found attempting to escape. By the time it reached me two crabs had escaped, a male and a berried female. These are most probably P.veterum. P.veterum is the pea-crab which inhabits the Pinna of the Mediterranean and is also found in the large Pinna of the Salcombe Estuary in Devonshire. It has been recorded as well from parts of the Irish coast in Pinna and Modiola. P.veterum. however,is much less common than P.pisum, the pea-crab which is found living within the mussel (Mytilus edulis) , as well as in other bivalve-molluscs. It so happened that the paper lining of the lid of the jar in which the ascidian and crabs travelled from Plymouth had become sodden and had fallen into the water in numerous small pieces. After the contents of the jar had been turned into a bowl and allowed to rest for a while, it was noticed that the crabs had hidden themselves beneath the paper. When uncovered they proceeded to hide themselves again, sidling under the fragments^ and throwing them on to their backs with their legs. The female being of considerable size (11 mm. in width) had more difficulty in hiding itself and made more use of its legs in placing pieces of paper on its back. Occasionally it was seen holding there fragments of paper, and once a tiny empty bivalve shell. The last two or three pairs of legs were used in these operations, and not the chelipeds, as perhaps one might have expected. The dactyli of the legs of this crab are long and curved. When in hiding the antennules were withdrawn. At night the crabs came out of hiding and were very active. The female appeared at dusk; the male some while, an hour or an hour and a half, later. The nights being very short in June, the crabs were only active for a few hours out of the twenty-four. The more tardy male never showed itself until 10.30 P.M., and was hidden again soon after daybreak, about 5 A.M. Summer Time.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.703633  DOI: Not available
Keywords: Zoology
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