Interambulacral plate, of Echinus esculentus, [511];

of Cidaridae, [533] f.;

of Echinarachnius parma, [544] f.

Interbrachial septa—see Interradial septa

Interchanges between cell and medium, [14]

Intermediate dorsal process of ciliated band of Auricularia, [608]

Intermediate (= supplemental) skeleton of Perforate Foraminiferal shell, [63], [66]

Intermittent fever, malarial, produced by Acystosporidae, [103] f.

Internal budding of Suctoria, [160] f., [162];

of Ephydatia, [177]