322 THE DOCTRINE OF DESCENT. 
1872), and Contributions to the Theory of Natural Selection (2nd 
ed. : 1871). 
56 “ The hypothesis of Pangenesis, as applied to the several great 
classes of facts just discussed, no doubt is extremely complex, but 
so assuredly are the facts. The assumptions, however, on whigh 
the hypothesis rests cannot be considered as complex in any 
extreme degree ; namely, that all organic units, besides having the 
power, as is generally admitted, of growing by self-division, throw 
off free and minute atoms of their contents, that is, gemmules. 
These multiply, and aggregate themselves into buds and the sexual 
elements ; their development depends on their union with other 
nascent cells, or units, and they are capable of transmission in a 
dormant state to successive generations. 
“Ina highly organised and complex animal, the gemmules thrown 
off from each different cell, or unit, throughout the body must be 
inconceivably numerous and minute. Each unit.of each part, as it 
changes during development—and we know that some insects 
undergo, at least, twenty metamorphoses—must throw off its 
gemmules. All organic beings, moreover, include many dormant 
gemmules derived from their grand-parents and more remote pro- 
genitors. ‘These almost infinitely numerous and minute gemmules 
must be included in each bud, ovule, spermaozoon, and pollen grain. 
Such an admission will be declared impossible, but, as previously 
remarked, number and size are only relative difficulties, and the 
eggs or seeds produced by certain animals or plants are so 
numerous that they cannot be grasped by the intellect.” Darwin, 
Variations of Animals and Plants, II. 526. ? 
57 A, Rollet, Ueber die Erscheinungsformen des Lebens und den 
beharrlichen Zeugen ihres Zusammenhanges. Almanach der kais. 
Akademie der Wissenschaften (Wien, 1872). 
58 Darwin, Variations of Animals and Plants, I. 200, 
69 V, Graber, Ueber den Tonapparat der Locustiden, ein Beitrag 
zum Darwinismus. Zeitschrift fiir wissenschaftliche Zoologie. 
Vol. 22. 
6 Hermann v. Nathusius, Vorstudien fiir Geschichte und Zucht 
der Hausthiere zundchst am Schweineschadel, 1864. 
STb., p. 108. 
® Descent of Man, I. 412. 
