ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 607 



been observed in any of the Coleoptera, the Acridida, Libellula, aculeate 

 Hyinenoptera, Muscidse, and all Lcpidoptera. 



7. When there is a pause it is almost always during the inspiratory 

 phases. 



8. In large forms, suitable for such investigation, it has been 

 observed that inspiration is ordinarily slower than expiration, and that 

 the latter is often very rapid. 



9. In most insects expiration only is an active movement, while 

 inspiration is passive, and due to the elasticity of the integument, and 

 of the walls of the tracheae. 



10. Inspiratory muscles are rare, but have been found in the 

 Phryganidte, as well as in the Hymenoptera and Acrididse. 



11. The so-called upper diaphragm, or alee cordis, as well as the 

 lower, have not the function attributed to them by Wolff. 



12. A large number of insects, perhaps all, impress on their 

 abdomen general movements, which vary in intensity, but do not 

 coincide with the respiratory movements proper. 



13. These last are purely reflex, and persist after decapitation, and 

 even (when the nervous system is not concentrated) when the abdomen 

 itself is isolated. In it the movements may be hastened or retarded by 

 just the same external causes as produce the same phenomena in the 

 uninjured animal. 



14. The metathoracic ganglia are not special respiratory 

 centres. 



15. The abolition of the respiratory movements, on the destruction 

 of the metathoracic ganglia, which is to be seen in Dytiscus and some 

 other Coleoptera, is due to the concentration of their nervous centres, 

 some abdominal being fused with the thoracic ganglia. 



16. In insects with a concentrated nervous system, the excitation 

 or partial destruction of a complex nervous mass affects all the centres 

 which enter into the composition of it. 



These important and interesting results are due partly to the use 

 of the " graphic method," the movements being inscribed on a rotating 

 blackened cylinder. In addition to this, a " method by projection " 

 was used. An insect fixed by a slight support, and in such a way 

 as not to affect its respiratory movements, is introduced into a large, 

 well-illuminated magic lantern. The objects of the investigation — 

 the respiratory movements — are then thrown upon a screen, whence 

 they can be drawn on a sheet of paper. Displacements of a fraction 

 of a millimetre can thus be followed. This latter method is a 

 modification of that of Professor Valerius. Further details will be 

 given in the complete memoir, of which this is only a preliminary 

 notice. 



Location of Taste in Insects.* — J. Kiinckel and J. Gazagnaire 

 have studied minutely the anatomy of the epipharynx (labrum of 

 authors) and hjpopliarynx in the Diptera. They form two troughs, 

 whose concavities are opposite each other, the hypopharynx being 

 embraced by the margins of the epipharynx. In Volucella the walls 



* Comptes Keudus, xciii. (18S1) pp. 347-50. 



