NO. 4 FEEDING MECHANISM OF LEPIDOPTERA SCHMITT 



^Z 



posterior bundle of which is shown by the position of the frontal con- 

 nective to be derived from the pharyngeal dilators. In addition to 

 these sheets of muscle, there are two pairs of dilators on the anterior 

 part of the pump. The dorsal salivarium muscles are well developed. 

 The sucking pump of Antographa falcifcra resembles that of Heliothis. 

 Arctiidae: Moths of this family are provided with poorly-developed 

 feeding mechanisms. Figure 6 C illustrates the head of an arctiid, 

 Apantcsis virgo. The pump muscles are mere strands, and the floor 

 of the pump is but weakly sclerotized. In Isia isabcUa the pump and 



dlcb- 



keel 



OcR 



Fig. II. — The sucking pump. 



A, right half of head, mesa! view, of Heliothis obsoleta, as exposed by median 

 sagittal cut. B, same of Samia cecropia. C, head of Epargyrcus tityrus, as seen 

 with dorsal wall removed. 



proboscis are weak but apparently functional. In the genus Haploa 

 the pump is relatively strong. Diacrisia virginica shows the most 

 degenerate condition observed in this family, the pump dilators being 

 mere strands. Yet, in many arctiids the dorsal salivarium muscles are 

 present and probably functional. 



Saturniidae: In this family the sucking pump is extremely weak. 

 Figure ii B illustrates the sucking pump of Samia cecropia. There 

 is a single pair of pharyngeal dilators, still recognizable by means of 

 the frontal ganglion. Laterally, there are two pairs of muscles which 

 might be functional. No salivarium muscles could be found. The 



