. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 20 OVUM. Fig. Campanularia geniculata (A and R from Loven, us copied by Steenstrup). A, modified or bell-shaped polype head or cap- sule, producing the female individuals at g,ff,g', the earliest of these budding from the granular stem g'. B, the female heads expanded from the bell: one of them containing two ova, o o; the other con- taining two ciliated embryoes, of which one is issu- ing at the summit of the attached medusoid, e e. c (from Schultze), male heads of the same spe- cies of Campanularia; p, upper part
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 20 OVUM. Fig. Campanularia geniculata (A and R from Loven, us copied by Steenstrup). A, modified or bell-shaped polype head or cap- sule, producing the female individuals at g,ff,g', the earliest of these budding from the granular stem g'. B, the female heads expanded from the bell: one of them containing two ova, o o; the other con- taining two ciliated embryoes, of which one is issu- ing at the summit of the attached medusoid, e e. c (from Schultze), male heads of the same spe- cies of Campanularia; p, upper part of the polype head, or bell-shaped capsule; c, sexual capsule, or modified attached Medusoid, containing spermato- zoa ; c', another of the same, burst, and spermatozoa discharged, s; c", other spermatic capsules advanc- ing behind the first. ledge of Desor's observations, and has farther proved the necessity of fecundation for the development of the ova so produced in the Campanularia geniculata (see fig. 15. C.). The various modes of production as they have been observed in the Tubularia by Van Beneden*, have been so fully detailed in the Article PoLVpiFERA,that the reader is referred to that article for an account of them. But it is to be observed that the reconversion of the Medusoid progeny of this animal into the Polype form described by that author (see Article POLYPIFERA,^. 50., p. 45.), has not received confirmation from the researches of other naturalists. Much remains still to be learned of this remarkable process; but enough has been ascertained to show that in a certain number of animals, usually known as passing the greater part of their lives in the Compound Polype condition, the state of sexual com- pleteness frequently belongs not to the Polype, but to a progeny having the form of a Medusa, and produced by a non-sexual process of de- velopment from the Polype stem. AculephfE.— Some time before the peculiar history of the development of the Polypina, now
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