The principal subject is the relations between ‘legs' and ‘prolegs'. With this end in view the muscles and their innervations in the metathorax and the ﬁrst three abdominal segments including their appendages have been dissected in six different larvae, viz. Hepialus humuli (L.), Monotrysia, Lep., Noctua pronuba L., Ditrysia, Lep., Tipula saginata Bergroth, Nematocera, Dipt., Arge pullata Zaddack, Chalastogastra, Hym., Tenebrio molitor L., Polyphaga, Col., Carabus nemoralis Müll., Adephaga, Col. Furthermore, the muscles and their innervations in the thoracic and the ﬁrst three abdominal segments in the imagines of Hepialus humuli and Noctua pronuba have been dissected. From these dissections it is concluded that the larval appendages, the prolegs, of the thorax and of the abdomen are homodynamous, since their motoric innervations are similar and originate exclusively from the ventral ganglionic nerves. In contrast the imaginal thoracic appendages, the legs, are innervated exclusively from the lateral ganglionic nerves. These results are compared with the ﬁndings of Réamur (1734), Kim (1952) and Kuske (1965) relative to the ontogeny of the imaginal legs. The possible afﬁnities of the prolegs are discussed. The close connection between the ontogeny of legs and wings is demonstrated in the pre-pupa of Tipula. The above conclusions are discussed and compared with the latest conclusions based on palaeontology.