𝔖 Bobbio Scriptorium
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Regeneration in polychœrus caudatus. Part I. Observations on living material

✍ Scribed by Stevens, N. M. ;Boring, A. M.


Book ID
102888396
Publisher
John Wiley and Sons
Year
1905
Tongue
English
Weight
735 KB
Volume
2
Category
Article
ISSN
0022-104X

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✦ Synopsis


While enjoying the hospitality of the Hopkins Seaside Laboratory at Pacific Grove, Cal., the past summer, I made a few experiments to test the powers of regeneration of the red acelous flatworm, Polychmrus caudatus, which abounds there in shallow tide-pools on the underside of stones and shells and on Ulva.

T h e object of the experiments was a comparison of the regeneration of this form which has no definitely differentiated organseyes, central nervous system, pharynx, etc.-with the more highly organized fresh-water Planarians, as well as with the results of Schultz ('02) and Child ('04) on Leptoplana and other marine forms which show very incomplete anterior regeneration.

Method.

I n most of the experiments, the worms were cut into three nearly equal parts as in Fig. A, a-b, c-d. These parts will be spoken of as head-pieces, middle-pieces and tail-pieces. T h e material was kept in covered glass dishes, somewhat shaded, and the sea-water was changed morning and evening.

Regeneration in general was much slower than in fresh-water Planarians. T h e animals are very sluggish normally, and the pieces moved but little even when disturbed by changing the water, the head-pieces, however, being much more active than the middle-pieces and tail-pieces. T h e tail-pieces continued to deposit eggs for several days as freely as did the entire worms, and the eggs developed normally.