336 PROCEEDINGS OF THE ACADEMY OF [Apr., 



favorable result. After the loss of the antennae, these insects reacted 

 almost as well as they did with their antennae intact. 



Porter (1883) thinks that the antennae of butterflies and some 

 other insects have nothing to do with olfaction. Some insects are 

 affected little, if at all, by the extirpation of the antennae, while 

 others become very sick after the loss of these appendages. 



Graber (1885) contends that ants {Formica rufa) and flies (Lucilia 

 coesar) and beetles {Silpha thoracica) without their antennae still 

 possess the sense of smell. He is inclined to the view that insects 

 do not have any special olfactory organ, and that when the odorifer- 

 ous emanations are intense they may be perceived by the surfaces 

 of the body which are covered with thin chitin and which are provided 

 with terminal excitable nerves. 



Plateau (1886) says that in Blatta the antennae are the olfactory 

 organs. Graber (1887) repeated Plateau's experiments by using 

 many cockroaches, and declares that in these insects the antennae 

 actually function as olfactory organs, but this is not true for all 

 insects. 



Fielde (1901, 1903, 1907) claims that the eleventh or distal segment 

 of the antennae of ants perceives the nest odor; the tenth segment, 

 the colony odor; the ninth segment, the individual track; the eighth 

 and seventh, the inert young; and the sixth and fifth, the odor of 

 enemies. Miss Fielde clipped the antennae with sharp scissors, and 

 15 days after the operation about 40 per cent, of the ants recovered 

 from the effect of the shock. "Before their recovery the ants were 

 listless and abnormally irritable; and they attacked with self- 

 destructive violence any moving thing that touched them." She 

 also found that queen ants deprived of their antennae did not behave 

 normally. 



Barrows (1907) says that gum on the antennae of Drosophila 

 ampelophila does not keep out odors, nor could the antennae be 

 burnt off without considerable injury to the flies. He etherized some 

 flies and cut off the terminal segment bearing sense cones with fine 

 scissors, and he declares that the ether did not affect the results of the 

 experiments with odors. He says: "It therefore seems certain 

 that the sense of smell is absent, or at least greatly reduced in flies 

 that have lost the terminal joints of the antennae." 



Kellogg (1907) informs us that male silkworm moths with extir- 

 pated antennae are unal)le to find the females unless by accident. 



From the foregoing it is seen that about one-fourth of all the 

 writers who have experimented on insects with nmtilated antennae 



