Published online by Cambridge University Press: 29 August 2010
The new views advanced by Weismann have, while these pages were going through the press, been subjects of warm discussion in England, where his essays have been translated and republished; but the subject has been so beclouded with technicalities and references to obscure facts of reproduction, that it is scarcely intelligible to non-technical readers. An explanation of the actual nature and bearing of these views may therefore be useful.
The subject may be regarded from the point of view either (1) of the facts of reproduction, or (2) of observed phenomena of inheritance.
1. With reference to the first of these, nothing is more certain than that in all animals, except a few of the lowest, there are special organs of reproduction, and that in these organs alone resides the power of permanent continuance of the species. The facts of budding and spontaneous division in some animals of low grade may be regarded as of only temporary importance. Farther, the organ of reproduction resolves itself into a single microscopic embryo cell or germ, a minute vesicle containing protoplasmic matter, fertilised by another or sperm-cell, and finally into the speck of protoplasm constituting the nucleus of this embryo cell. This minute living speck must contain in it potentially all the parts and organs that are produced from it. Weismann illustrates this in a clear manner by the observed fact of the spontaneous division of this nucleus into a vast number of separate granules, each of which plays a part in the formation of some portion of the embryo animal.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.