Chap. XXVII. 



OF PANGENESIS. 359 



attended to this subject, shows in detail that there is sometimes 

 "a compromise between self-division and budding." When a 

 limb is amputated, or when the whole body is bisected, the cut 

 extremities are said to bud forth ; and as the papilla, which is 

 first formed, consists of undeveloped cellular tissue like that 

 forming an ordinary bud, the expression is apparently correct. 

 We see the connection of the two processes in another way ; for 

 Trembley observed that with the hydra the reproduction of the 

 head after amputation was checked as soon as the animal began 

 to bud. 3 



Between the production, by fissiparous generation, of two or 

 more complete individuals, and the repair of even a very slight 

 injury, we have, as remarked in a former chapter, so perfect 

 and insensible a gradation, that it is impossible to doubt that 

 they are connected processes. Between the power which re- 

 pairs a trifling injury in any part, and the power which pre- 

 viously "was occupied in its maintenance by the continued 

 " mutation of its particles," there cannot be any great difference ; 

 and we may follow Mr. Paget in believing them to be the self- 

 same power. As at each stage of growth an amputated part 

 is replaced by one in the same state of development, we 

 must likewise follow Mr. Paget in admitting " that the powers 

 "of development from the embryo are identical with those 

 "exercised for the restoration from injuries: in other words, 

 "that the powers are the same by which perfection is first 

 " achieved, and by which, when lost, it is recovered." 4 Finally, 

 we may conclude that the several forms of gemmation, and of 

 fissiparous generation, the repair of injuries, the maintenance 

 of each part in its proper state, and the growth or progressive 

 development of the whole structure of the embryo, are all 

 essentially the results of one and the same great power. 



Sexual Generation.— The union of the two sexual elements 

 seems to make a broad distinction between sexual and asexual 

 reproduction. But the well-ascertained cases of Parthenogenesis 

 prove that the distinction is not really so great as it at first 

 appears; for ovules occasionally, and even in some cases fre- 

 quently, become developed into perfect beings, without the con- 



•3 Paget, ' Lectures on Pathology/ 1853, p. 158. 4 Idem> pp> 152> 164> 



