1911] Knab — Food Habits of Megarhinus 81 



E. E. Green controverts the idea that Megarhinus immisericors, 

 the "stinging elephant mosquito" before mentioned, bites. "I 

 have never experienced its bite, nor have I been able to induce 

 it to bite me by method ssuccessful with other biting Culicidse."^ 

 Very significant is the fact that within the last few years, when 

 general attention has been directed to mosquitoes, no observations 

 confirmatory of blood-sucking have appeared although Megarhinus 

 have been recorded repeatedly as entering houses. 



The most forcible evidence that Megarhinus does not suck blood 

 lies in the structure of its proboscis. While all the parts found 

 in the females of the blood-sucking species are present, the sheath, 

 or labium, is strongly chitinized and rigid. This is not the case 

 with the blood-sucking forms. The part played by the com- 

 ponents of the proboscis when a mosquito pierces the skin has 

 been common knowledge since the days of the immortal Reaumur 

 and need not be discussed here at length. When the lancets 

 are forced into the skin the sheath is pushed back and bent into 

 a loop, and in this way the piercing parts are made to protrude 

 beyond the tip of the proboscis to perforate the skin. It is there- 

 fore perfectly evident that Megarhinus, with its rigid proboscis 

 sheath, cannot pierce the skin. 



For those to whom the structure of the proboscis is not con- 

 vincing it may be further stated that of a considerable number 

 of Megarhinus which have come to hand not one shows traces 

 of a blood-meal. Furthermore, in collections the males far out- 

 number the females, a goodly proportion of the species being 

 known from the male alone, a condition the reverse of what obtains 

 with the blood-sucking species. 



Probably the first direct observation recorded, of a Megarhinus 

 feeding, was that by the writer (1. c.) of a female M. septentrionalis 

 sucking honey from the flowers of Hydrangea arborescens. Since 

 then observations of Megarhinus visiting flowers for food have 

 been made both in the eastern and the western hemisphere. 

 I owe the following observations, which demonstrate very clearly 

 that Megarhinus are honey-feeders, to the kindness of the well- 

 known entomologist, F. W. Urich of the Board of Agriculture 

 of Trinidad, British West Indies, sent under the dates of 1 Nov. 

 and 6 Dec, 1910. "I had a rather good find a few days ago in 



» Spolia Zeylanica, vol. 2, p. 159-160 (1905). 



