1915] Lovell — Origin of Antkophily among the Coleopfera 79 



is also shorter and more robust; in Strangalia again the elongated 

 thorax is correlated with a long slender abdomen.^ While the 

 cylindrical forms of these beetles are an advantage in visiting 

 flowers, the genera of the Lepturini were probably essentially 

 differentiated before they became anthophilous. The influence of 

 insect economy in modifying the structure of the head and thorax 

 is well illustrated by the Rhyncophora, which are, as has been 

 shown, of little significance in poUination. The front of the head is 

 prolonged into a slender beak, and in some species the head behind 

 the eyes is constricted into a neck, and the thorax is elongated and 

 narrowed anteriorly. But in this group it is clear that the mor- 

 phology of the head and thorax was very early determined in its 

 phylogenetic history by the habit of excavating the little pits in 

 which the eggs are laid. 



But in the genera Gnathium and Nemognatha of the Meloidse 

 there occur undoubted modifications of the mouthparts for obtain- 

 ing nectar. The blister beetles at times appear suddenly, and 

 Epicauta vittata may destroy large areas of tomatoes and potatoes 

 in a few days. An extended list of the plants on which these 

 beetles feed is given by Gibson in the fourty-second annual report 

 of the Entomological Society of Ontario. In New England only 

 three species of this family have been observed on flowers, but 

 Epicauta pennsylvanica is very common on the flowers on Solidago. 

 Gnathium and Nemognatha, southern and western genera living 

 wholly on nectar, have the maxillae prolonged into a slender suc- 

 torial tube, resembling a lepidoterid tongue. The length of this 

 suctorial tube has been measured in 14 species of Nemognatha, and 

 showed a gradual increase from 1.5 mm. to 10 mm. in length, pre- 

 senting a complete series of intermediate gradations." N. vittigera, 

 according to Graenicher, visits the flowers of the Compositse 

 exclusively, chiefly those of Rudbeckia hirta. This observer 

 states that the behavior of these beetles when at work on flowers 

 presents additional evidence of a high degree of adaptation, the 

 tongue being thrust in and removed from the florets with great 



1 This view is favored by Cockerell's observations on the bee genus Perdita. He states that 

 the length of the tongue appears to have increased or decreased according as the total size of the 

 bee has increased or decreased, not to meet special requirements. "The Bees of the Genus 

 Perdita," Proc. Acad. Nat. Sci. Philadelphia, Vol. 48, p. 40. 



2Graenicher, S., "On the Habits of Beetles of the Genus Nemognatha," Ent. News, Vol. 21, 

 pp. 72-75. 



