94 Proceedings of the Royal Physical Society. 



the movement was repeated and then with gradual shortening of the 

 interval and increase of the activity, a stage marked by vigorous and rapid 

 movement of the limbs was arrived at, without, however, appearing to cause 

 any stretching of the deutovum membrane. Up to this time the rostrum, 

 which was folded under the body, remained passive, but it now gradually 

 extended itself at right angles to the body and in doing so stretched the 

 membrane considerably. The next stage was to get the rostrum extended 

 anteriorly in line with the body, thereby stretching the membrane still more, 

 and when this was accomplished the palpi began to move vigorously. Before 

 long the strong claws with which they are equipped caused several rents in 

 the membrane, and with the rupture of this the creature made its escape to 

 begin the first free stage of its existence. In all the cases observed by me 

 the membrane was colourless and was ruptured at its anterior end, but the 

 time from the first evidence of motion to the escape of the larva, varied 

 considerably in each case. 



With regard to the occurrence of Piona camea referred to above, I found 

 it was not restricted to any one part of the loch, but was distributed all over 

 it. This I connected with the immense number of Entomostraca to be found 

 in every part of the loch. Indeed the number was so great as to become a 

 nuisance, necessitating the net being cleared of a handful of Entomostraca 

 every few minutes. 



I am obliged to Dr Thos. Scott, F.L.S., for naming the Eurycypris for me. 



(Issued separately, 2StA April 1910.) 



