THE HISTORY OF ANATOMICAL SCIENCE 321 
dude that Owen’s labours in the field of mor- ' 
phology were lost, because they have yielded little 
fruit of the kind he looked for. On the contrary, 
they not only did a great deal of good by awaken- 
ing attention to the higher problems of morphology 
in this country ; but they were of much service in 
clarifying and improving anatomical nomencla- 
ture, especially in respect of the vertebral region. 
Apart from questions of classification, the only 
special work of Owen, which deals directly with 
the greater problems of biology, is the discourse on 
‘ Parthenogenesis, or the Successive Production 
of Procreating Individuals from a single Ovum,’ 
originally delivered in the form of the opening 
two lectures of the Hunterian Course for 1849. 
In these discourses, an attempt is made to cor- 
relate, and furnish an explanation of, thephenomena 
of sexless proliferation ; that is to say, of the pro- 
duction of offspring by a plant or an animal, with- 
out the intervention of sex. In the vegetable 
world, such phenomena, as exemplified by the 
growth and detachment of buds or bulbs, or 
of young plants, like those formed on strawberry 
‘runners,’ have been known from time imme- 
morial ; among animals, they were first carefully 
elucidated by Trembley and Bonnet in the 
middle of the eighteenth century. 
One of the commonest and most striking cases 
is that of the plant lice, or Aphides, which are the 
commonest of pests in our gardens. The young, 
VOL. II. Y 
