42 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [BuU. 



It is of interest to note that the loss of an arm does not cause 

 even a temporary diminution in the rate of growth, the rest of 

 the body increasing in size as rapidly as in the case of uninjured 

 individuals. Even the loss of two arms has little efifect. The 

 lost arms are rapidly replaced if food is abundant, and in their 

 regeneration grow faster than the others until the normal sym- 

 metry of the body is restored. 



Fig. 3. Outlines of two starfishes of the same age 

 (SJ4 weeks), showing diflference in the rate of growth 

 under the influence of diflferent food supplies. (After 

 Mead.) 



The age at which the starfish becomes sexually mature iS' 

 also influenced by the rate of growth, for Mead has found that 

 all starfishes with a lengfth of ray of more than 50 mm. at the 

 beginning of the breeding season, in May, are sexually mature, 

 while others, but 10 or 15 mm. long at the same date, do not 

 deposit sexual products until the following year. Now the 

 length of 50 mm. is reached by well nourished individuals when 

 less than four months of age, so that it seems reasonable to con- 

 clude that the well fed starfishes are ready to breed when a little 

 less than one year old; that is, in June of their first year. 



The rate of growth is most rapid during the warmer months 

 of the year, and may cease entirely during the winter. This is 

 probably due in part to the smaller amount of food devoured, 

 and in part to the development of the sexual products. 



