Miscellaneous. 235 the embryo Vorticella, it is stated that its pulsations were less rapid than in the full-formed animalcule ; a circumstance at variance with analogy; for, in the embryos of higher animals, the contractions of the cardiac vesicle, or punctum saliens, are more frequent than those of the circulating sac in the adult. Moreover. if such a perfect system of organs, presenting a cardiac and a respiratory sac, be observable in the Vorticella, it must surely elevate that genus

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... ably in the scale of animals, and place it far above the majority of the polygastric Infusoria. And, consequently, if such a complex or-