GUADALUPIA ZITTELIANA n. sp. (p. 80).

The typical specimen. The convexity suggests that this sponge is a cylindrical body broken at the sides, but while broken away above for an indefinite distance the lateral outlines are very nearly those of the entire organism.

Side view.

Tangential section through the outer layer, X 5.

Tangential section through the outer layer, X 5. The section is more or less diagonal. Along the upper margin a spicular network is shown, more distinct than in 1a. In the center are the transversely cut ends of several mural tubes.

Tangential section through the mural tubes, X 5.

Section longitudinally through the mural tubes, X 5.

Capitan formation, Capitan Peak (station 2926).

A small specimen referred with doubt to this species. Both upper and lower surfaces are retained.

Side view.

Upper side from which the dermal layer has been partially eroded.

Lower side showing thickened area of attachment.

Capitan formation, Capitan Peak (station 2926).

GUADALUPIA CYLINDRICA n. sp. (p. 81).

The typical specimen.

Transverse section across the organism, cutting the mural tubes more or less longitudinally. The interior is partially filled by an irregular cystose growth which is probably. intrinsic. The dark dots in the walls of the mural tubes may be sections through spicules, X 5.

Longitudinal section through the organism, longitudinal also through the mural tubes. Here too is shown the partial filling of the interior by irregular cystose structures. A few of the tubes in this, as in the preceding section, will be observed to be crossed by diaphragms, X 5.

Tangential section very near the periphery. The spicular network of the outer layers is shown and the transversely cut ends of some of the mural tubes, X 5.

Side view of the nearly characterless specimen from whose upper end the foregoing sections were made.

Capitan formation, Capitan Peak (station 2926).

GUADALUPIA CYLINDRICA var. CONCRETA n. var. (p. 82).

The typical specimen.

Side view.

End view, showing the area of attachment to some striated organism, possibly a Productus.

View of upper surface, showing the tubes in part bifoliate and in part radiating from different centers.

Capitan formation, Capitan Peak (station 2926).

GUADALUPIA sp. (p. 84).

An organism of doubtful affinities embedded in rock.

Side view.

Capitan formation, peak north of Pine Spring (station 2902).