306 



REPORT ON ZOOLOGY, MDCCCXLIV. 



the Silkworm the author discovered bony corpuscles, in the form of star- 

 shaped cells, exactly like those of the human body. 



Leon Dufour (Compt. rend, xix, 188) persists in de- 

 claring the German naturalists in error who profess to have 

 observed a circulation in insects, although the existence 

 even of a closed vascular system, in insects breathing by 

 tracheae, is now established beyond dispute. 



Kiister assigns to the feelers (antennae) of insects the 

 function of smelling. (Isis, 647.) 



This opinion is grounded upon the following experiments. Some pure 

 spirit of turpentine having been dropped iipon small pieces of paper, these 

 were placed in glass cylinders, and captured insects were introduced. In a 

 few minutes they appeared very uneasy, rubbing their feelers frequently, 

 while the parts of the mouth were also in action, and the kinds with a trunk 

 protruded it. By degrees the movements became slower, the feelers which 

 had begun to droop at the end, especially if they were long, lost at last the 

 power of straightening, and, after a stupor of from ten to twelve hours, death 

 ensued. The author then gives a series of observations on the varying 

 degrees of sensibility to the smell of turpentine, in different insects, always 

 with reference to the comparative development of the antennae. This fre- 

 quently is in an inverse ratio to that of the eyes, as in the Cicindelida? and 

 Carabidre. In accordance with this, the Carabidse showed more sensibility 

 to the smell of turpentine, and their antennae drooped very quickly so far as 

 the pubescence on them extends. So of the Cerambycidte. The Buprestida: 

 have very little, the Elateridse, on the contrary, very great irritability, and 

 above all the males with pectinated feelers. The author considers the 

 structure of these organs in the Hymenoptera as strongly corroborative of 

 his theory, and the insects of this order betrayed great sensibility to the 

 vapour of turpentine. In Spiders the author is disposed to consider the 

 enlarged palps of the males as an organ of smell highly developed for the 

 discovery of the other sex ; but it has been demonstrated already that these 

 parts have a different function. (Report 1843, p. 195.) 



If these experiments show that the feelers betray a sensibility to the 

 effect of powerful odours, it is not yet proved that these act on them directly, 

 and so the evidence that the sense of smell has its seat in the feelers is 

 defective. In regard to this the fine downy coat with which they are often 

 clothed demands particular attention. 



Siebold has published his investigations into the organ 

 of hearing in some Orthoptera. (Ueber das Stinim- und 



