EMBRYOLOGY OF ANIMALS....continued

Sea Urchin Embryology: Unfertilized eggs - Fertilized eggs - Two cells - Four cells - Eight cells - Sixteen cells - Thirty-two cells - Morula - Blastula - Blastula, beginning gastrulation - Blastula, progressive gastrulation - Pluteus larva - Sea urchin embryology, schematic graphic colour designs of all stages.

Embryology of the Frog: Uncleaved egg with jelly envelop, view to the animal pole, egg spot and polar bodies, w.m. - Beginning first division, grey crescent visible, w.m. - Two-cell stage, egg not yet completely separated, w.m. - Two-cell stage, t.s. - Four-cell stage, second groove vertical to the first one, w.m. - Four-cell stage, t.s. - Eight-cell stage, four micromeres and four macromeres, w.m. - Median section through the sixteen-cell stage - Morula, w.m. - Morula, median section, blastocoel can be seen - Blastula, w.m. - Blastula, median section, blastocoel - Gastrula, w.m. blastopore appears semicircular - Gastrula, frontal section - Early neurula, detailed view of t.s. with neural plate and primitive gut - Early neurula, w.m., the neural folds get closer - Late neurula, w.m., neural folds are closed - Late neurula, detailed view of t.s. with neural tube, somites, chorda and coelom - Early tail bud stage, eye cleft and optic stalk - Sagittal section through early neurula - Middle tail bud stage, primordia of gills - Middle tail bud stage, primordia of gills and leg bud - Tail bud stage, sagittal l.s. with forebrain, neural tube, notochord, digestive tract, heart - Tail bud stage, parasagittal l.s. showing primitive segments - Hatching stage of embryo, t.s. through head showing brain, eyes - Hatching stage of embryo, t.s. through region of heart - Newly hatched larva, w.m. shows fully developed adhesive processes, gill plumes - Newly hatched larva, parasagittal l.s. showing pronephros, Wolffian duct - Larva, t.s. through region of eyes - Larva, t.s. through region of heart - Larva, t.s. in region of stomach showing primordia of liver and stomach, pronephros and spinal cord - Older larva, frontal section through eye region, gill arches and gill clefts - Frog, the cleavage divisions, colour schematic designs - Frog, the Gastrulation, total views and sagittal sections. Schematic designs of several stages - Frog, the neurulation, dorsal views and transverse sections. Schematic designs of several stages - Frog, schematic design of the early gastrula, showing the position of the germ layers and the primordia, various organs.

Embryology of the Chicken: 24 hour, w.m. showing primitive groove, primitive node, 7 somites, and neural plate - 24 hour, t.s. through primitive groove showing formation of mesoderm - 24 hour, t.s. showing neural plate, notochord, mesoderm - 28 hour, w.m. 10 somites, primordium of heart and eyes, notochord - 36 hour, t.s. of posterior region of abdomen shows neural groove, notochord, and mesoderm - 36 hour, t.s. of anterior region of abdomen showing neural tube, notochord, the mesoderm forming myotome and splanchnotome - 40 hour, w.m. 15 somites, heart, primordium of brain - 45 hour, l.s. shows primitive node, formation of mesoderm and somites, heart, brain - 48 hour, t.s. of abdomen. Myotome, nephrotome, and splanchnotome - 50 hour, w.m. shows heart, primordium of brain and eyes, auditory vesicles, buccal cavity - 72 hour, w.m. injected to show the blood vascular system: Heart, gill vessels, aorta, venous system, extraembryonic vessels - 3 days, t.s. through posterior region of abdomen showing coelomic cavities, nephrotome - 3 days, t.s. through region of head. Primordium of brain and eyes, gill arches - 4 days, t.s. of anterior region of abdomen, pronephros, Wolff’s duct - 4 days, t.s. in region of heart, primordium of wings and vertebrae - 5 days, w.m. showing formation of head, eyes, limb buds, gill arches, allantois - 8 days, l.s. with primordium of organs, heart, liver, metanephros, brain - Gallus, feather development, sec. through wings in stages of the development - Gallus, skin of body, horizontal section shows t.s. of feather quills - Gallus, t.s. through embryo of 48 and 72 hours, colour graphic design.