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doi: 10.1111/j.1096-3642.1942.tb00053.xpmid: N/A
1 A description is given of the colony of Arctic Terns {Sterna macrura Naumann) which was present in the spring of 1938 in St. Cuthbert's Cove on the Inner Fame Island, off the coast of Northumberland. About a thousand pairs of these birds were present, and they nested with equal success on several different types of ground. 2 The eggs and young in this large colony were, on the average, much further advanced in development than were those in smaller colonies present on other islands. 3 The behaviour of the birds to each other and to other species was recorded, and the pairs were shown to possess their own small breeding territories. The limits of these territories, after a period of learning, were also observed by the young birds up to and even after the time when they had begun to fly. 4 The structure of the Arctic Tern colonies is compared with that of the colonies of other species of seabirds, and a series of examples is quoted which shows the increasing enslavement of the individual birds to a communal nesting system.
doi: 10.1111/j.1096-3642.1942.tb00054.xpmid: N/A
The reduction of the hind wings in Ptinus tectus Boield takes place exclusively during the pupal period. It is caused primarily by the necrosis of cells throughout the whole extent of the wing epithelia; some part may also be played by a failure of the remaining cells to expand normally towards the end of the pupal period, but this is uncertain.
doi: 10.1111/j.1096-3642.1942.tb00055.xpmid: N/A
1 The burrowing process has two phases–a simple scraping away of the soil by the hind foot, and at intervals another action which results in the sudden ejection of loosened soil over the back of the retreating animal. 2 The burrows have the openings closed, and are not used a second time. 3 Emergence does not occur on every night. 4 Emergence occurs most often on wet nights, even in terraria not exposed to the rain. 5 Emergence is independent of temperature, temperature changes, light, time elapsing since the last sight of daylight, hunger, defaecation, urination, carbon dioxide changes, humidity, odours of night air. It occurs at the normal time in toads hermetically sealed in darkened jars in a thermostat. 6 Emergence varies with the time of sunset. 7 Emergence in animals transported round one quarter of the circumference of the earth occurs at the local time and not in the evening of the country of origin. It is therefore not a 24‐hour rhythm, but is externally determined. 8 There is plenty of air for the animals in their closed burrows, and respiratory metabolism is not suspended or reduced beyond the normal reduction in resting animals. 9 Even in animals which remain buried there is more C02 produced at night than by day. This rhythm is not shown in toads kept long in captivity. 10 The paper records facts but does not postulate hypotheses, and points out that no explanation is at hand of the manner in which environmental changes are conveyed to the buried animals. 11 A classification of animal rhythms is proposed.
doi: 10.1111/j.1096-3642.1942.tb00056.xpmid: N/A
1 A series of pituitaries of teleosts from a number of orders have been examined. A nervous lobe and a glandular component of three regions, typically confluent but distinct, is present in all. 2 The form of the nervous lobe and its penetration into the glandular regions is described, and the variations in the relations of the various parts to each other and to the brain. Their histological features, blood supply, relative sizes and degree of confluence, and their diagnostic characters are summarized. 3 Systematic position has been found to entail a considerable degree of similarity in the glands as far as orders and families are concerned, but it is only possible to trace the evolution of the gland within the group to a very minor extent. 4 The homology of the various subdivisions of the gland with those of higher types is indicated and a possible relationship between them through lung‐fish and ganoids is suggested.
Jackson, C. H. N.; Vanuerplank, F. L.
doi: 10.1111/j.1096-3642.1942.tb00057.xpmid: N/A
1 We have measured the corpuscles in dried blood films of over 200 individual mammals, mostly wild East African forms, belonging to about 40 species. 2 There is not a great deal of variation within the species, but specific measurements vary from about 3 to 9 microns. 3 Our results agree fairly well with those of Lloyd and Johnson. 4 Closely related species, unless we consider the impala as a gazelle, have corpuscles of about the same size.
Moreau, R. E.; Pakenham, R. H. W.
doi: 10.1111/j.1096-3642.1942.tb00058.xpmid: N/A
During the long period that elapsed between the submission of this paper and its publication a certain amount of further taxonomic and field‐work on the island faunas continued, the results being communicated by the authors from time to time in order that when the paper eventually appeared it should be as complete and up to date as possible. Owing to the war, the authors, both resident in East Africa, u‐ere naturally unable to see the proof of their paper, and when it eventually reached them in published form it became obvious that one of their communications, containing the bulk of the amendments given below, had failed to reach the Editor and so had failed to be incorporated f.
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