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INVERTEBRATES

 

to that of many of the latter. They occur sporadic-ally in large numbers in pools that become dry during the summer months. Like so many of the fresh water animals they have resistant eggs which can withstand drought and frost and which are doubtless transported long distances by water birds.

Pristicephalus gelidus (Hay)—Scarboro Junction. Lynceus gouldii (Baird)—Scarboro Junction. Eulimnadia agassizii Packard—Georgian Bay.*

 

Cladocera.

These minute water fleas flourish in abundance in fresh water everywhere. They form the chief food of the fry of many of our fishes. They are often seen swimming around in immense swarms. The only record is

Daphnia pulex ?—Tap-water (Acheson).

 

Ostracoda.

An examination of debris from the margin or bottom of any pool or stream will show numbers of these minute shelled Crustaceans scrambling over the other objects. The only record for Toronto is a Cypris (?) sp. by Nicholson.

 

Copepoda.

These " oar-footed " water fleas are found in a variety of situations in our fresh waters. Best known is " the little Cyclops with one eye " that can be

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