n EXPERIMENTS ON STARVING 77 



weak to thrive unless considerable variations also occur 

 in their mode of life ; or their fertility may be very 

 much impaired, and thus the species is liable to go to 

 ruin. Thus it seems that, as things are, the condition 

 of every species including under this word condition 

 the state of all parts of the organism is exactly what 

 it should be to meet the present external circum- 

 stances, and departures from this condition are possible 

 only when necessary to the species itself, through a 

 change in circumstances. Concerning decrease in 

 dimensions, we may note that while a continuous 

 decrease must surely end in death, there are cases 

 where a large loss may be sustained without bringing 

 about this result. I made some experiments on this 

 point, a few years ago, and obtained the following 

 results. Wishing to ascertain the loss of weight 

 which animals are able to sustain without losing their 

 life, I weighed a number of Invertebrates, crabs and 

 medusae among others, and kept them in pure sea- 

 water without any chance to get anything to eat, 

 although I have reason to suspect some more enter- 

 prising individuals did eat some of their brethren. 

 But many mishaps befell this experiment, in one way 

 or another the course of true experiment seldom runs 

 smooth and at the end of a fortnight most of my 

 animals were gone, so that, in order to prevent a 

 complete disaster, I preferred stopping the process and 



