146 + Mr. W.S. MacLeay on the Anatomy of the 
counteracted in time, and as you ask me for such a paper, I hope what 
I now send will answer your purposes. 
Yours ever most truly, 
W. S. MacLeay. 
Havana, 2nd October, 1829. 
I find it impossible to give, according to the present state of the science 
in England, any satisfactory description of insects, without making some 
previous observations on their anatomical nomenclature. My object now 
therefore is to explain to entomologists a few of the principles by which 
I shall be guided in my future descriptions. 
Eight years have elapsed since the second part of the “« Hore Entomo- 
logice’’ was published. In this work I gave incidentally an outline of the 
theory of comparative anatomy so far as it related to the subkingdom of 
Annulosa, and as it was known at the time. Since then indeed three 
works have appeared, all treating of this most difficult subject with more 
or less philosophical rigour and critical acumen, but all three apparently 
having very different objects in view. 
The first of these in point of patient labour are the very ingenious and 
detailed memoirs of M. Chabrier on the Anatomy of the Organs of Flight 
in various Insects, which were published in the ‘ Mémoires du Muséum 
** d’ Histoire Naturelle.” The object of these memoirs is not to givea 
strictly comparative view of the anatomy, so much as to shew the internal 
and external structure of the various organs that have an influence on the 
flight of insects, This isa work therefore rather important for the infor- 
mation it affords as to facts, than for the generalization of them. 
Immediately afterwards M. Audouin published in the first volume of 
the “ Annales des Sciences Naturelles’’* the first part of his “ Recherches 
* Anatomiques sur le Thorax des Animaux Articulés, et celui des Insectes 
“« Hexapodes en particulier,” which researches he announced it to be his 
intention to continue in the same Journal. They had long before been 
laid on the table of the Institute, indeed previously to the appearance of 
M. Chabrier’s Mémoires, and had been most favorably reported on by 
M. Cuvier as the president of a commission appointed to examine them.t 
* Published in 1824, 
+ See Rapport fait A ’Académie des Sciences de Paris dans la Séance du 
