✦ LIBER ✦

The origin of the test-cells of ascidians

✍ Scribed by T. H. Morgan

Publisher: John Wiley and Sons
Year: 1890
Tongue: English
Weight: 662 KB
Volume: 4
Category: Article
ISSN: 0362-2525
DOI: 10.1002/jmor.1050040204

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✦ Synopsis

WORD of explanation and apology seems necessary on adding another account to the long list of descriptions of the origin of the test-cells. While studying the embryology of CZavelZina in the spring of 1888, I became interested in the origin of the test-cells, and the work was continued during the summer of the same year. A preliminary note was written in October, '88, and published in the Johns Hopkins University Circular, Vol. VIII., No. 72.

A t the same time I obtained the paper of Van Beneden and Julin in tlie Archives de Biologie, Tome, VI., '87, in which I found conclusions almost exactly similar to thwe to which I had come. It seemed then unnecessary to publish a full account of the work, and the figures and descriptions were laid aside.

In the spring of '89, Dr. M. v. Davidoff published a new account of the origin of the test-cells (Mittheilungen aus der Zoologischen Station zu Neapel), in which he differs essentially from Van Beneden and Julin. Thus the whole question became once

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