A contribution to the anatomy of growth in earthworms

✍ Scribed by Gairdner B. Moment

• Publisher: John Wiley and Sons
• Year: 1950
• Tongue: English
• Weight: 636 KB
• Volume: 86
• Category: Article
• ISSN: 0362-2525
• DOI: 10.1002/jmor.1050860105

✦ Synopsis

Earlierework has shown that in the common manure-pile worm or brandling, Eiserzia foetida, the number of segmknts regenerated posteriorly from any cut surface between the 40th and the 80th segment is numerically limited. This liniitation is of such a nature that the formation of new segments at the posterior tip of the worm stops when the total number of segments old and new summates to approximately 90 (Moment, '46). This fact has now been confirmed on worms kept at a constant temperature of 25°C. (See table 1.) The worms used in this newer work were from a locality some 8 miles from that previously used. Otherwise all the techniques and conditions were the same as in the earlier experiments save only that the temperature was held constant at 25°C.

The marked contrast between the close correlation in nuniber of segments regenerated and level of the cut, and complete lack of any correlation between either the length of the worm in millimeters, or the original number of segments, or even the reproductive condition of the worm and the number of segments regenerated is illustrated in figure 1. The groups of