VIEWS AS TO THE ORGANS OF SMELL 265 



special frontal holes of flies and Orthoptera, etc., while Bonsdorf considered the 

 palpi as organs of smell. 



Thus four different views, confused, were held at the opening of this century ; 

 the Hamburg zoologist, M. C. S. Lehrman, in three different treatises, brought 

 together all the hitherto known observations and arguments, treated them criti- 

 cally, and completed them by his own extended studies. Lehrman adopted the 

 opinions of Heimarus, Baster, Dume'ril, and Schelver, that the stigmata presented 

 the most convenient place for the site of the organs of smell. Cuvier followed 

 throughout the lead of Lehrman, but Latreille returned to the view of the per- 

 ception of smell by the antennae, while Treviranus considered the mouth of 

 arthropods as the probable site of the sense of smell, an opinion which, before 

 his time, Huber, in his experiments on bees, had thought to be correct. Marcel 

 de Serres (1811) returned again to the palpi, and asserted at least in the 

 Orthoptera their functions to be olfactory, while Blainville, ten years later, 

 again expressed anew the old opinion that the antenna, or at least their termina- 

 tions, were organs of smell. Up to that date there was an uncertainty as to the 

 seat of the organs both of smell and hearing. Fabricius, indeed, had already, 

 in 1783, thought he had found an organ of hearing at the base of the outer 

 antenna. In 1826 J. Miiller mentioned an already well-known organ in the 

 abdomen of crickets as an organ of hearing. Miiller, however, was doubtful, 

 from the fact that the nerve passing to this organ arose, not from the brain, but 

 from the third thoracic ganglion; but, notwithstanding, he remarks: "Perhaps 

 we have not found the organ of hearing in insects because we sought for it in 

 the head." This discovery was afterwards considerably broadened and ex- 

 tended by Siebold's work, for the views of these naturalists on the seat of both 

 organs had a definite influence, especially in Germany. For awhile, indeed, 

 Miiller's hypothesis stood in complete contradiction, so that during the following 

 decennial was presented anew the picture of opposing observations and opinions 

 as to the nature of the organs of smell. While Kobineau-Desvoidy, at the end 

 of the twentieth year, and also later, in different writings, strove energetically 

 for the olfactory nature of the antennae, Straus- Diirckheim held fast to the view 

 that the tracheae possessed the function under discussion. At the same period 

 Kirby and Spence, in their valuable Introduction to Entomology, maintained 

 that "two white cushions on the under side of the upper lip" in the mouth of 

 biting insects formed a nose or " rhinarium " peculiar to insects. This opinion 

 was afterwards adopted by Lacordaire (Introduction a Entomologie), and also 

 by Oken in his Lehrbuch der Naturphilosophie, while Burmeister, rejecting all 

 the views previously held, believed that insects might perhaps smell "with the 

 inner upper surface of the skin." Miiller's locust's ear he regarded as a vocal 

 organ. 



Besides these occasional expressions of opinion, the French literature of the 

 thirtieth and fortieth years of this century recorded a long series of special 

 works, with weighty experimental and physiological contents, on this subject. 

 Tims Lefebre, in 1838, described the experiments which he made on bees, and 

 which seemed to assign the seat of the sense of smell to the antennas. Duges 

 reported similar researches on the Scolopendne, and Pierret thought that the 

 great development of the antennas in the male Bombycidse might be similarly 

 interpreted. Driesch sought to give currency to the views of Bonsdorf, Lamarck, 

 and Marcel de Serres, that the sense of smell was localized in the palpi, though 

 Duponchel went back to the old assertion of seroscepsis of Lehrman, i.e. of the 

 air-test through the antennae, and Goureau again referred the seat of the sense 

 of smell to the mouth. In England, Newport at this period put forth a work in 

 which he considered the antennae as organs of touch and hearing, and the palpi 



