12. PREDATORS AND PARASITES
373
determine their sex but it can be deduced from his data that it was the
small females and large males that were parasitized. This could only
be effected if the parasites caused the males and females to grow a t
different rates. Also, all parasitized animals were approaching an age of
1 year, no 2 year olds having been found to be parasitized. Since it is
hard to believe that the parasite has a free living stage which is present
in the sea for 9 or 10 months of the year it suggests that the late larval
stage euphausiids eat the " spores " and these lie dormant in the tissues
until the following spring when they increase in size and become
noticeable. Future investigations may, of course, modify these ideas.
373
determine their sex but it can be deduced from his data that it was the
small females and large males that were parasitized. This could only
be effected if the parasites caused the males and females to grow a t
different rates. Also, all parasitized animals were approaching an age of
1 year, no 2 year olds having been found to be parasitized. Since it is
hard to believe that the parasite has a free living stage which is present
in the sea for 9 or 10 months of the year it suggests that the late larval
stage euphausiids eat the " spores " and these lie dormant in the tissues
until the following spring when they increase in size and become
noticeable. Future investigations may, of course, modify these ideas.