48 
BULLETIN OF THE BUREAU OF FISHERIES 
cease feeding and in that event also become emaciated and gradually acquire a soft 
shell. The sudden change in the rate of growth of animals that have made little or 
no growth is further discussed in connection with the brood of 1912. 
Animals in hibernation, of course, make no growth, but subsist upon foods stored 
within the body. Such animals are poor when they emerge and generally have to 
feed for a month or more, as already stated, before perceptible growth is made. 
This is especially true of terrapins in their first year, and that is one of the reasons 
why winter feeding of recently hatched young appears to be profitable. 
77? 7 ? ?. 
Figdre 4.— Rate of growth of a selected lot of the brood of 1913 
The rate of growth of the winter-fed lots while in the nursery house — that is, 
until they are about 8 months old — has varied greatly, as shown by Table 20. The 
small lot of the brood of 1910, consisting of only 173 animals, the first one fed during 
the winter, was among the best produced to date (1928); for the average length of 
the terrapins was 39.7 millimeters (representing a gain of 11.6 millimeters) when 
they were removed from winter quarters on May 10, 1911 (Table 22). Small lots 
of 100 or so, held in separate compartments in the terrapin house, have done equally 
