Dr. Papp Jenő szerk.: Folia Entomologica Hungarica 25/8-35. (Budapest, 1972)

within the head capsule and further four muaolea occur ventrally all in typical poaitionso The innervation of these ia done by the sympathetic but in certain cases one branch of the central nervous system may also appear. The following muscles may be < called typical /Figo 1/: m 42: musculua dilatator pharyngis frontalis m 43: muaculua retractor angulorum oris m 44: musculus dilatator pharyngis postfrontalis m 45: musculus dilatator postpharyngeal is TT! 46: musculua longitudinális atomodaei m 47: musculus anularis atomodaei m 48: musculus transversalis buccae ventralis m 49: musculus transversalis buccae dorsalis m 50: musculus dilatator pharyngis lateralis m 51: musculus dilatator cayi buccalis m 52: musculus dilatator cibarii m 53: musculus dilatator pharyngis ventralis m 54: musculus dilatator buccalis ventralis m 55: musculus dilatator pharyngis ventrolateralis ra 56: musculus dilatator ventrolateralis m 57: musculus reticularis oesophagei The muscles of the pharynx and oesophagus in fact can be divided into two groups, /i/ the various muscles of the pharyngeal wall and /ii/ the suspending muscles of the pharynx. The latter, without exception, originate on the solid elements and inner surface of the head capsule and adhere on the wall of the pharynx and oesophagus. They play a role besides an elastic auapension,in swallowing; their sympathetic innervation ensures the passing ôf the food which to a certain extent is mechanical and peristaltic in nature. In insects the greater part of the sympathetic nervous aystem ia aituated in the head, but, as it has been mentioned above, ita typization may be carried out with utmoat difficulty only due to the diatribution of the homologization of individual parta. In brief, the sympathetic nervous system is extremely variable and polymorphic. In apite of thia, aa it is shown in Figs. 2 and 3 the following may summarize what is common in them.