 | 1895 - Страниц: 1314
...the blastoderm cells. The pocket remains open but a short time, but there is a long depresssion of the upper end of the bunch of cells ; the mass of...from a portion which is later to become ectoderm.' " Alimentary Canal in Orthoptera. — Dr. F. Werner has compared* the relative length of the intestine... | |
 | 1895 - Страниц: 1336
...stages show that these cells produce the generative organs ; the generative organs thus appear to he produced by an infolding of the ectoderm, or possibly...from a portion which is later to become ectoderm.' " Alimentary Canal in Orthoptera. — Dr. F. Werner has compared* the relative length of the intestine... | |
 | 1895 - Страниц: 1272
...the blastoderm cells. The pocket remains open but a short time, but there is a long depresssion of the upper end of the bunch of cells ; the mass of...from a portion which is later to become ectoderm.' " Alimentary Canal in Orthoptera. — Dr. F. Werner has compared* the relative length of the intestine... | |
 | James William Tutt - 1899 - Страниц: 582
...grey matter which originally bordered the whole egg, but which became a part of the blastoderm cells. The pocket remains open but a short time, but there...1866, showed for certain insects a different origin." Those further interested in the details of this subject would do well to refer to the writer's chapter... | |
 | Robert Wilhelm Hegner - 1909 - Страниц: 102
...posterior end ; these cells remained "in contact with the ventral plate at the place where they are produced. Later stages show that these cells produce...blastoderm before the ectoderm is produced but from a position which is later to become ectoderm." In a nine and a half day embryo of Pieris cratcegi, Graber... | |
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The pocket remains open but a short time, but there is a long depresssion of the upper end of the bunch of cells ; the mass of cells is soon cut off from the ventral plate and they are then free in the body cavity, but remain in contact with the ventral... 