A preliminary report on the Protozoa of the fresh waters of Connecticut / by Herbert William Conn.

  • Herbert William Conn
Date:
1905
Catalogue details

Licence: In copyright

Credit: A preliminary report on the Protozoa of the fresh waters of Connecticut / by Herbert William Conn. Source: Wellcome Collection.

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    found. In the study of Protozoa careful figures are always of more value to the microscopist than specific descriptions, because of the difficulty in studying the animals and tracing out minute details. It frequently happens that one can easily recognize a species from its appearance, when it would be impossible to determine the characters upon which the species or even the genus is based. In the study of a rapidly moving microscopic animal it is often impossible to make out minute details, and points in internal structure, — like the nucleus and vacuoles — cannot, in many cases, be decided upon in the living specimens. In all such cases the general appearance of the animals is of more use in determination than specific descriptions. For this reason there is given, in the present report, a figure of every species of animal thus far thoroughly identified, and, in some cases, two or three figures of the same type are given where specimens show considerable variations from each other. The figures are all original, and drawn by the author from the actual specimens. The key printed in this preliminary report is designed for the use of working students, and is not intended to indicate any real relations of the organisms in question. The problem of the general relations of the groups will be discussed when a more complete report of the Protozoa may be prepared. This key is based upon one which has been found most useful to the author, namely, the one published by Kirchner and Bloch- mann.* The key, as printed in the following pages, follows in general the one devised by these authors. It has, how- ever, been much modified, to make it clearer and more useful to a beginner. Inasmuch as quite a number of genera are clearly present in our waters which are not included in the above-mentioned key, it has been found necessary to add these new genera to the key. It is believed, therefore, that our key is an improvement over any before published. This key in- cludes all the genera known to occur in fresh water, whether they have yet been detected in Connecticut or not, and, conse- quently, all that are likely to be found in our State. * Die Mikroskopische Pflanzen- und Thierwelt des Susswassers, Braun- schweig, 1886.
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