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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 haveobserved a circulation in insects, although the existenceeven of a closed vascular system, in insects breathing bytracheae, is now established beyond dispute.

Kiister assigns to the feelers (antennae) of insects thefunction of smelling. (Isis, 647.)

This opinion is grounded upon the following experiments. Some purespirit of turpentine having been dropped upon small pieces of paper, thesewere placed in glass cylinders, and captured insects were introduced. In afew minutes they appeared very uneasy, rubbing their feelers frequently,while the parts of the mouth were also in action, and the kinds with a trunkprotruded it. By degrees the movements became slower, the feelers whichhad begun to droop at the end, especially if they were long, lost at last thepower of straightening, and, after a stupor of from ten to twelve hours, deathensued. The author then gives a series of observations on the varyingdegrees of sensibility to the smell of turpentine, in different insects, alwayswith reference to the comparative development of the antennae. This fre-quently is in an inverse ratio to that of the eyes, as in the Cicindelidse andCarabidee. In accordance with this, the Carabidse showed more sensibilityto the smell of turpentine, and their antennae drooped very quickly so far asthe pubescence on them extends. So of the Cerambycidae . The Buprestidaihave very little, the Elaterid®, on the contrary, very great irritability, andabove all the males with pectinated feelers. The author considers thestructure of these organs in the Hymenoptera as strongly corroborative ofhis theory, and the insects of this order betrayed great sensibility to thevapour of turpentine. In Spiders the author is disposed to consider theenlarged palps of the males as an organ of smell highly developed for thediscovery of the other sex; but it has been demonstrated already that theseparts have a different function. (Report 1843, p. 195.)

If these experiments show that the feelers betray a sensibility to theeffect 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 isdefective. In regard to this the fine downy coat with which they are oftenclothed demands particular attention.

Siebold has published his investigations into the organof hearing in some Orthoptera . (Ueber das Stimm- und