Interactions morphogènes au cours de l'histogenèse du corpuscule de Herbst, étudiées à l'aide de transplantations hétérochrones
Morphogenetic interactions during the histogenesis of Herbst's corpuscle, as studied by heterochronic transplantations Duck embryo frontal buds or bill fragments have been transplanted to the frontal bud or limb bud of early duck embryo hosts. Results show that: (1) Somato-sensory nerve endings are able to participate in corpuscle histogenesis as soon as they reach 14 days of incubation. (2) However, corpuscle histogenesis can take place only in dermis that is older than 20 days of incubation. (3) The time at which the corpuscles form in a graft of a given age is independent of the total duration of graft innervation. The results, which demonstrate the existence of morphogenetic interactions between the dermal mesenchyme and the nerve endings, are discussed in connexion with what is known about the origin of Herbst's corpuscle and the role of nerve and cutaneous tissue in its development. A schematic model is proposed for the morphogenetic sequence of Herbst's corpuscle.