A small piece of the surface of a living coenobium, seen from the surface. Only four individuals are visible, the central capsule of which contains numerous small nuclei and a central oil-globule. The including spherical lattice-shell is provided with a few (one to four) larger apertures, which are prolonged into short cylindrical tubules. Through these latter radiate bundles of fine pseudopodia, branching and anastomosing, and forming a fine sarcode network between the alveoles of the calymma. On the surface of the alveolated jelly-sphere the pseudopodia form a dense radiating zone. Xanthella or yellow cells are everywhere scattered. Fig. 2. _Siphonosphæra socialis_, n. sp., × 300 106 A small coenobium or colony in the state of alveolation, forming a jelly-sphere, composed of a great number of capsulated individuals, densely aggregated. Each central capsule contains an oil-globule, and is enclosed by a spherical lattice-shell, which bears a few (one to four) short cylindrical tubules. Each shell is again enveloped by a membranous polyhedral alveole and separated from it by structureless jelly. The thick cortical jelly-envelope, which surrounds the whole spherical colony, exhibits a fine radial striation, produced by radiating pseudopodia; many xanthellæ or yellow cells are scattered in the calymma. Fig. 3. _Siphonosphæra pipetta_, n. sp., × 300 108 Fig. 4. _Siphonosphæra tubulosa_, J. Müller, × 300 105 The central capsule, enclosed in the cavity of the shell, has a central oil-globule, and is surrounded by a few xanthella. Fig. 5. _Siphonosphæra chonophora_, n. sp., × 300 107 Fig. 6. _Siphonosphæra serpula_, n. sp., × 300 107 Fig. 7. _Siphonosphæra patinaria_, n sp., × 300 105 The central capsule, enclosed in the cavity of the shell, contains a central oil-globule, and is surrounded by a few xanthella. Fig. 8. _Siphonosphæra patinaria_, n. sp., × 300 105 Fig. 9. _Siphonosphæra conifera_, n. sp., × 300 106 Fig. 10. _Siphonosphæra cyathina_, n. sp., × 300 105 [Illustration: SIPHONOSPHAERA.] PLATE 7. LEGION SPUMELLARIA. Order SPHÆROIDEA. Family COLLOSPHÆRIDA. Fig. 1 _Caminosphæra dendrophora_, n. sp., × 300 112 Fig. 2. _Caminosphæra dichotoma_, n. sp., × 300 112 Fig. 3. _Coronosphæra diadema_, n. sp., × 300 117 Fig. 4. _Coronosphæra calycina_, n. sp., × 300 117 Fig. 5. _Otosphæra auriculata_, n. sp., × 300 116 Fig. 6. _Otosphæra polymorpha_, n. sp., × 300 116