Page:The Works of William Harvey (part 1 of 2).djvu/651



"Four kinds of bodies" are enumerated by Hieronymus Fabricius "as existing externally to the fœtus; these are the umbilical vessels, the membranes, the humours, and a fleshy substance." On these subjects, guided by my observations, I shall briefly state wherein I differ from him; first, however, giving his statement in his own words.

"There are," he says, "three membranes, two of which envelope the whole fœtus, but the third does not do so. Of those which envelope the whole fœtus, the innermost, immediately investing one, is called i.e. the mantle. That which follows next is entitled by the Greeks ; the Latins, however, have not given it a name, although some interpreters have thought proper erroneously to call it "secundæ" or "secundina," the secundines; this also envelopes the entire fœtus. The third is called, i.e. gut-like, from its resemblance to a stuffed intestine; it does not entirely encompass the fœtus, but is applied upon the thorax and part of the abdomen, and extends to either horn of the uterus." He allows that this last membrane is only found in the fœtus of the sheep and cow; he asserts also that it is continuous with the urachus, and by means of this receives the urine from the bladder. Hence, he goes on, "horned animals, in whom this allantois is found, have the urachus so wide and straight, that it resembles a small intestine; it gradually decreases in size until it reaches the fundus of the bladder; whence it would appear to owe its