Embryology of insects and myriapods; Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching embryologyofinse00joha Year: 1941 398 EMBRYOLOGY OF INSECTS AND MYRIAFODS muscles, and a dorsal and ventral trachea pass. The recurrent nerve arising from the posterior end of the bridge owes its origin to ganglion cells which developed from the median dorsal wall of the stomodaeum where it remains under the muscle layer. At the time the cardioblasts meet on the middorsal line, small cells are liberated from the ectoder
Embryology of insects and myriapods; Embryology of insects and myriapods; the developmental history of insects, centipedes, and millepedes from egg desposition [!] to hatching embryologyofinse00joha Year: 1941 398 EMBRYOLOGY OF INSECTS AND MYRIAFODS muscles, and a dorsal and ventral trachea pass. The recurrent nerve arising from the posterior end of the bridge owes its origin to ganglion cells which developed from the median dorsal wall of the stomodaeum where it remains under the muscle layer. At the time the cardioblasts meet on the middorsal line, small cells are liberated from the ectoderm immediately above the heart to form a nerve that later attaches itself to the heart (Fig. 349, dr). This nerve is formed independent of either the central nervous or the visceral systems. The Tomosvary sense organs connected with the brain and located in the head have been described for Scolopendra, Glomeris, Lithohius, and fg Fig. —Scolopendra cingulata. Cross section of foetal head, {ao) Aorta. (Jg) Neuropile of frontal ganglion, {ggl) Ganglion cells, {md) Mandible, {mus) Muscle. {neur. pi) Neuropile of deutocerebrum. {neur. p2) Neuropile of frontal lobe. {op. n) Optic nerve, (tdm) Tomosvary organ, {torn, n) Tomosvary nerve. {Adapted from Heymons.) other myriapod genera. In Scolojpendra the organ is closely associated with the development of the frontal lobes of the forebrain. Near the frontal lobes, which owe their origin to the lateral brain pits, there is an inward migration of some cells that closely resemble those of the frontal lobes and that remain attached to the epidermis for a time. These cells represent the anlage of the Tomosvary organ. As development proceeds, the organ loses its connection with the surface but retains its connection with the frontal lobe by means of a string of cells. This string becomes the Tomosvary nerve which joins the brain at the junc- tion of the optic and frontal lobes (Fig. 354, torn. n). The function of these o
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