IV.] MINUTE MODIFICATIONS. 115 



species being distinct) is by reversion, owing to a supposed 

 ancestral cross. But he candidly admits, " I have heard of 

 no other such case in the animal or vegetable kingdom." 

 On the supposition of its being only a variety, he observes, 

 "The case is the most remarkable ever recorded of the 

 abrupt appearance of a- new form, which so closely re- 

 sembles a true species, that it has deceived one of the most 

 experienced of living ornithologists." 



As to plants, M. C. Naudin 18 has given the following 

 instances of the sudden origination of apparently perma- 

 nent forms : " The first case mentioned is that of a poppy, 

 which took on a remarkable variation in its fruit a crown 

 of secondary capsules being added to the normal central 

 capsule. A field of such poppies was grown, and M. G6p- 

 pert, with seed from this field, obtained still this monstrous 

 form in great quantity. Deformities of ferns are sometimes 

 sought after by fern-growers. They are now always ob- 

 tained by taking spores from the abnormal parts of the 

 monstrous fern ; from which spores ferns presenting the 

 same peculiarities invariably grow. . . . The most remark- 

 able case is that observed by Dr. Godron, of Nancy. In 

 1861 that botanist observed, among a sowing of Datura, 

 tatula, the fruits of which are very spinous, a single indi- 

 vidual of which the capsule was perfectly smooth. The 

 seeds taken from this plant all furnished plants having the 

 character of this individual. The fifth and sixth generations 

 are now growing without exhibiting the least tendency to 

 revert to the spinous form. More remarkable still, when 

 crossed with the normal Datura tatula, hybrids were pro- 

 duced, which, in the second generation, reverted to the 

 original types, as true hybrids do." 



There are, then, abundant instances to prove that con- 

 siderable modifications may suddenly develop themselves, 



16 Extracted by J. J. Murphy, vol. L, p. 197, from the Quarterly Jour- 

 nal of Science, of October, 1867, p. 527. 



