Fig. 2. _Medusetta quadrigata_, n. sp., × 400 1668 The central capsule is visible in the upper half, the phæodium in the lower half of the shell-cavity. Fig. 3. _Medusetta tetranema_, n. sp., × 400 1669 Fig. 4. _Medusetta craspedota_, n. sp., × 400 1669 Fig. 5. _Gazelletta hexanema_, n. sp., × 300 1671 Fig. 6. _Gazelletta bifurca_, n. sp., × 300 1672 A single alveolate foot. Fig. 7. _Gazelletta macronema_, n. sp., × 200 1671 Oral view of the shell. Fig. 8. _Gazelletta macronema_, n. sp., × 800 1671 Three joints of an alveolate foot. Fig. 9. _Gazelletta cyrtonema_, n. sp., × 300 1671 The upper part of the shell encloses the central capsule with its nucleus. The voluminous phæodium is prominent over the mouth. Fig. 10. _Gazelletta orthonema_, n. sp., × 200 1671 The central capsule and its nucleus are visible in the shell-cavity. Fig. 11. _Gazelletta schleinitzii_, n. sp., × 400 1673 Oblique apical view, with the enclosed central capsule, the nucleus of which contains numerous nucleoli. Fig. 12. _Gazelletta schleinitzii_, n. sp., × 300 1673 A single alveolate foot. Fig. 13. _Gazelletta trispathilla_, n. sp., × 400 1673 The middle part of a foot. Fig. 14. _Gazellatta robusta_, n. sp., × 300 1673 The base of a foot, exhibiting the pores of the alveoli. Fig. 15. _Gazelletta studeri_, n. sp., × 400 1673 The distal end of a foot; four alveoli filled up by air-bubbles. Fig. 16. _Gazelletta dendronema_, n. sp., × 300 1674 A part of the velum, seen from the inside. The alveoles are partly filled by air. [Illustration: 1.-4. MEDUSETTA, 5.-16. GAZELLETTA.] PLATE 121. LEGION PHÆODARIA. Order PHÆOCONCHIA. Family COELODENDRIDA. Fig. 1. _Coelodendrum furcatissimum_, n. sp., × 50 1735 A complete specimen with the central capsule and the big phæodium. The spherical calymma envelops almost the entire skeleton. Fig. 2. _Coelodendrum furcatissimum_, n. sp., × 300 1735 A distal branch with its terminal ramification. Fig. 3. _Coelodendrum furcatissimum_, n. sp., × 100 1735 One valve of the shell, with its galea and the four hollow forked tubes arising from it. Fig. 4. _Coelodendrum furcatissimum_, n. sp., × 100 1735 The central capsule with its nucleus; on the left side one valve of the closely enveloping shell (seen in vertical section), and its galea with the origin of the four tubes. Fig. 5. _Coelodendrum serratum_, n. sp., × 400 1737