On the Composition of Cassiopea Xomachnna. 



103 



EXPERIMENTS ON STARVATION. 



LOSS OF WEIGHT IN STARVING CASSIOPEA. 



Eight freshly caught normal cassiopeas having different body- weights 

 were subjected to starvation by placing them in filtered sea- water. 

 The filtration was effected with all the precautions adopted by Mayer 

 (1914) and the water (4,500 c.c.) in the vessel was changed once every 

 day. The period of starvation was 21 days and the body- weights were 

 taken every day for the first 6 days and then at 10 and 21 days. The 

 loss of weight is shown in table 4. 



TABLE 4. Loss of weight in starving Casswpeas. 



These eight cassiopeas were divided into three groups composed of 

 the three largest, the three medium, and the two smallest individuals 

 respectively. The object of such grouping was to see whether or not 

 the loss differed according to the size of the animal. Table 4 shows a 

 distinct difference in the loss according to the initial body-weight. In 

 general, the smaller cassiopeas lost relatively much more than did the 

 larger (see table 5) . This result agrees with the results found for the 

 starving vertebrates. It is remarkable, however, that cassiopeas after 

 losing nearly 62 to 80 per cent of their initial body-weight appear in 

 no respect different from the normal cassiopea of similar body-weight. 

 It is very difficult to distinguish the starved from the normal by merely 

 looking at them unless the velar lobes happen to be turned upward 

 as occurs in some of the cassiopeas after several days of starvation. 



