Africa and OutlyingIslands, On a Collection of Birds Made by Mr. Willoughby P. Lowe on the West Coast of, David Armitage Bannerman (bibliog.

That an increase in the temperature of the medium, within limits, accelerates the embryonic development of fishes has been adequately demonstrated by several investigators. This was studied by Dannerig (1895), by Reibisch (1902), by Apstein (1909), and by Johansen and Krogh (1914) in several species of Pleuronectes and in Gadus morrhua. The development of two Japanese fishes, Hypomesus olidus and Plecoglossus altivelis, has been observed from this standpoint by Higurashi andTauti (1926), andKawajiri (1927) records similar data for the Japanese trout (Oncorhynchus mason).The development of the mackerel (Scomber scombrus L.) has not previously been examined from this point of view. A detailed study of the relation of temperature to the rate of development of the egg of this fish from the time of its fertilization until hatching was undertaken during the mackerel spawning seasons of 1931 and 1932 at the Woods Hole, Massachusetts, Station of the United States Bureau of Fisheries.It was especially desirable to record as accurately as possible the time necessary at different constant temperatures for the attainment of various embryonic stages of development, as well as the time required for hatching. Secondarily, it was interesting to determine the upper and lower temperature limits for typical development. Some information regarding mortality and survival at different temperatures was also obtained. MethodsOrdinary fish hatching boxes were employed as constant temperature water baths. Reasonable insulation for the thermostat is afforded by the walls of the * Published with the approval of the Commissioner of Fisheries.

No abstract

It is now generally known that the typical locomotor movements of an infusorian depend upon not less than three attributes of the organism's cilia-the ciliary beat, ciliary metachronism and ciliary reversal. So intimately associated are these three activities that they have been spoken of together as "coordinated movements of the animal as a whole" and they are often referred to in a manner which suggests that they are under the control of a single mechanism within the cell. This is not surprising since reversal and metachronism are such universal characteristics of beating protozoan cilia.The mechanism by means of which the coordinated movement of the simple cilia of an infusorian is effected is not known. At one time it was more or less generally believed that the cilia of Paramecium were under the control of a ' neuromotor apparatus,' a system of endoplasmic fibres reaching the cilia from a 'motorium' located near the nuclens (Rees, '22). However, no physiological evidence in support of this opinion has been brought forth since the time these structures were first described, and the recent tendency is to look elsewhere for a coordination device. Accordinly, the