[2.] A portion (about 1/10th of an inch square) of the surface of attachment of the peduncle of Pollicipes polymerus, seen from the outside, greatly magnified, showing the small circular (bb) patches of cement, poured out from the cement-ducts (aa) which lie within the peduncle.

[2a´.] A portion of a section, still more magnified, through the basal membrane of the peduncle, through one of the loops of the cement-ducts (aa), and through one of the circular patches (b) of cement.

[3.] Cement gland, duct, and ovarian tubes of Conchoderma aurita; (aa), ovarian tubes, with ova in process of formation; (b), cement-gland; (c), cement-duct.

[4.] [Conchoderma virgata], enlarged, with one side of the capitulum and of the peduncle removed, to show the form and position of the body.

(a.) tergum, edge of.

(b.) mouth, with one of the palpi seen on the inner, upper corner.

(c.) adductor scutorum muscle.

(d.) orifice of acoustic (?) sack.

(e.) scutum, occludent margin of.

(f.) branching ovarian tubes within the peduncle.