The effect of heteroplastic grafts of the spinal cord on the development of the limb of Amblystoma

✍ Scribed by Wieman, H. L.

• Publisher: John Wiley and Sons
• Year: 1926
• Tongue: English
• Weight: 733 KB
• Volume: 45
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1400450113

✦ Synopsis

When a lieteroplastic graft of the fore-limb rudiment is carried out in Amblystoma tigrinum and Amblystoma punctatum, the results are in a general way in keeping with the inherent potentialities of the limb buds of the two species with, however, certain interesting and unlooked-for departures from the expected results. Thus Harrison ('24) found that when the fore-limb rudiment of punctatum is excised and the corresponding limb rudiment of tigrinum is engrafted, the latter eventually grows to a greater size than if left undisturbed in its normal position. Since tigrinum is a larger animal than punctatum, one would expect the engrafted tigrinum limb to become larger than its punctatum mate, but not to exceed the size of the normal tigrinum limb. I n the extreme case the linear dimensions of the grafted limb are said to be fully double those of the normal a t the time of metamorphosis, which is as f a r as observations have been carried. I n the reciprocal graft, when the limb bud of punctatum is grafted to tigrinum, the grafted limb lags behind normal punctatum limb until late in larval life, when it finally overtakes and surpasses the normal in size.

The present experiments were undertaken with the intention of testing the effects of reciprocal innervation on the development of the limb bud in these two species, by leaving the limb buds undisturbed, but interchanging the limb Ievel 335