THE 



ZOOLOGICAL JOURNAL. 



Fehruary — June, 1830. 



Art. XXVI. Explanation of the Comparative Anatomy of 

 the Thorax in IFinged Insects, ivilh a Revieiv of the present 

 state of the Nomenclature of its parts. By W. S. Mac- 

 Lkay, Esg., A.M., F.L.S., ^c. 



My dear Vigors, 

 The enclosed in fact belongs to the Third Part of the " HorcB Entomo- 

 logies,''^ entitled "./^n Analytical Essay on the Developenient of Annu- 

 " lose Forms ;^' * but as the receipt of some of the late publications from 

 England makes me sorry that errors should acquire strength by not being 



* It has been thought that this Essay is to be confined to the description of 

 the structure of Larvae. My intention, however, is, that it should embrace the 

 developenient of the whole Annulose Structure, whether in the Larva, Pupa, 

 or Imago state. To those friends who have of late urged me to give a second 

 edition of the first volume of the " Horce Entomologicce" I take the opportunity 

 of saying, that this will probably never be done, at least under the same form ; 

 — a form, which, however convenient for the purpose of making known the 

 results of my various investigations in the shape of Essays, is not such as I 

 would choose, were I to state those investigations a second time to the ento- 

 mological world. For instance, the First Part of the " Hor(E Entomologies," 

 although it led the way to the researches explained iu the Second Part, ought 

 hereafter, in fact, to follow them. The form of the work, however, is too 

 convenient to be abandoned by a naturalist whose other occupations will only 

 permit his making, from time to time, detached Essays ; and this must be my 

 only apology for intending to continue a work, of which the first volume is in 

 so few hands, and of which a second edition will probably never be published. 



Vol. V. K 



