The seed offers another striking example; the Palaeozoic seeds (if we leave the seed-like organs of certain Lycopods out of consideration) were always, so far as we know, highly complex structures, with an elaborate vascular system, a pollen-chamber, and often a much-differentiated testa. In the present day such seeds exist only in a few Gymnosperms which retain their ancient characters--in all the higher Spermophytes the structure is very much simplified, and this holds good even in the Coniferae, where there is no countervailing complication of ovary and stigma.英文原著 · 《Darwin and Modern Science》
None of the early Ferns show any clear approach to other classes of Vascular Cryptogams; so far as the fossil record affords any evidence, Ferns have always been plants with relatively large and usually compound leaves. There is no indication of their derivation from a microphyllous ancestry, though, as we shall see, there is some slight evidence for the converse hypothesis. Whatever the origin of the Ferns may have been it is hidden in the older rocks.英文原著 · 《Darwin and Modern Science》
The general conclusions to which we are led by a consideration of the fossil record of the Vascular Cryptogams are still very hypothetical, but may be provisionally stated as follows:英文原著 · 《Darwin and Modern Science》
The Matonineae are ferns with an unusually complex vascular system and were abundant "in the northern hemisphere during the earlier part of the Mesozoic era."英文原著 · 《Darwin and Modern Science》
"I've read of such cases. It's a calcareous enlargement of the vascular bony tissue, threatening ossification," said the doctor.英文原著 · 《Queer Little Folks》
"Yes, a morbid tendency often found in these cases of bony tumification of the vascular tissue of the mouth; but you must resist it, ma'am, as their life depends upon it." And with that Dr. Peppercorn glared gloomily on the young ducks, who were stealthily poking the objectionable little spoon-bills out from under their mother's feathers.英文原著 · 《Queer Little Folks》
Kenny's girlfriend wanted to go to see a movie afterwards, but I just got the second edition of Chaikof's "Atlas of Vascular Therapy" so decided not to go.美剧 · 《The Good Doctor》
Possible acute vascular response, circulatory collapse -- And what about on D.I.C.?美剧 · 《The Good Doctor》
You place the vascular blood vessel lining cells on the inside. You place the vascular blood vessel lining cells on the inside.演讲 · 《Growing new organs ~ Anthony Atala》