332
G. V. LOPASHOV AND O. G.
STROEVA
rudiment. The lens which focuses light, and part of the cornea, arise
from the ectodermal covering of the embryo, while the eye envelopes
and the blood vessels arise from the mesenchyme. The latter also
participates in the formation of the iris and the connective tissue stroma
of the cornea. How are all these parts interrelated in development and
how is the correlation realized in the formation of an entire organ which
is so amazingly well adapted to the performance of its function? This
problem may be solved by a wide application of the experimental
method. The studies of the dependence of lens formation on the primary
eye rudiment initiated a fruitful series of investigations, associated
with the discovery of embryonic induction. Much time has elapsed
since this first experimental work, and experimental embryologists are
now in possession of many facts on the development of the eye.
It now seems to be timely to summarize the results in order to perceive the whole modern picture of investigations on the development of
the eye and to outline some pathways for further advance. This chapter
is aimed at this purpose. It does not embrace the entire relevant literature but aims only to distinguish the main data which can be used to
draw some general conclusions. Lack of space requires us to concentrate
on the morphogenesis of the eye itself, leaving out the development of
its appendages, such as eye muscles and lids. The mechanisms of the
dimensional correlations of the eye and the rest of the body (Harrison,
1929, 1935; Twitty, 1940, 1955), as well as the action of hormones on the
development of the eye successfully investigated recently by Wald
(1958) and Wilt (1959) will not be considered. The origin of congenital
malformations of the eye will be discussed only when they can be related to sufficiently analysed mechanisms of development. We shall not
expatiate on the history of the problem, though we must mention the
pioneering work of Spemann (1901, 1905) and Lewis (1904, 1905,
1907) in their investigations of lens and cornea induction, which provided a basis for causal embryology in general. A thorough analysis of
other processes in the development of the eye started much later. It was
Adelmann (1929, 1930) who first carried out systematic and exact
investigations on their origin of the eye rudiments within the neural
plate, while Dragomirov (1932, 1933a, 1935) can be credited with
initiating the study of their segregation into retina and pigment epithelium. Before the work of these authors the problems in question
were discussed only on the basis of fortuitous and inexact observations
obtained mainly in experiments carried out with some other aim in
view. Finally, inethe field of the study of regeneration of the retina and
lens, which we shall not analyse specially, the crucial point arose from
the work of Wachs (1914,1920), followed later by that of Stone (1950a, b).
The most important monographs and reviews devoted to the eye and
G. V. LOPASHOV AND O. G.
STROEVA
rudiment. The lens which focuses light, and part of the cornea, arise
from the ectodermal covering of the embryo, while the eye envelopes
and the blood vessels arise from the mesenchyme. The latter also
participates in the formation of the iris and the connective tissue stroma
of the cornea. How are all these parts interrelated in development and
how is the correlation realized in the formation of an entire organ which
is so amazingly well adapted to the performance of its function? This
problem may be solved by a wide application of the experimental
method. The studies of the dependence of lens formation on the primary
eye rudiment initiated a fruitful series of investigations, associated
with the discovery of embryonic induction. Much time has elapsed
since this first experimental work, and experimental embryologists are
now in possession of many facts on the development of the eye.
It now seems to be timely to summarize the results in order to perceive the whole modern picture of investigations on the development of
the eye and to outline some pathways for further advance. This chapter
is aimed at this purpose. It does not embrace the entire relevant literature but aims only to distinguish the main data which can be used to
draw some general conclusions. Lack of space requires us to concentrate
on the morphogenesis of the eye itself, leaving out the development of
its appendages, such as eye muscles and lids. The mechanisms of the
dimensional correlations of the eye and the rest of the body (Harrison,
1929, 1935; Twitty, 1940, 1955), as well as the action of hormones on the
development of the eye successfully investigated recently by Wald
(1958) and Wilt (1959) will not be considered. The origin of congenital
malformations of the eye will be discussed only when they can be related to sufficiently analysed mechanisms of development. We shall not
expatiate on the history of the problem, though we must mention the
pioneering work of Spemann (1901, 1905) and Lewis (1904, 1905,
1907) in their investigations of lens and cornea induction, which provided a basis for causal embryology in general. A thorough analysis of
other processes in the development of the eye started much later. It was
Adelmann (1929, 1930) who first carried out systematic and exact
investigations on their origin of the eye rudiments within the neural
plate, while Dragomirov (1932, 1933a, 1935) can be credited with
initiating the study of their segregation into retina and pigment epithelium. Before the work of these authors the problems in question
were discussed only on the basis of fortuitous and inexact observations
obtained mainly in experiments carried out with some other aim in
view. Finally, inethe field of the study of regeneration of the retina and
lens, which we shall not analyse specially, the crucial point arose from
the work of Wachs (1914,1920), followed later by that of Stone (1950a, b).
The most important monographs and reviews devoted to the eye and