178 Mr. W. 8S. MacLeay on the Anatomy of the 
little variation, not only gives a complete philosophical and harmonious 
view of the construction of the thorax, but reduces the number of words 
used to express 52 pieces to 11; surely a most important consideration 
when itis borne in mind how great an obstacle to the study of natural his- 
tory isa cumbersome load of anatomical words. I shall always endea- 
vour to proceed on similar principles of symmetry and condensation in 
my future papers where I may have to investigate the anatomy of the 
head, wings, abdomen, and legs. In the mean time, if on no other 
ground than that of priority, I indulge strong hopes that Mr. Kirby will, 
in a new edition of his useful Introduction, see the advantage of returning 
to M. Audouin’s nomenclature of the parts of the thorax, while Mr. West- 
wood, or some other of our acute entomologists, will throw light on the 
structure of our British Insects by subjecting the different genera to the 
above kind of comparative scrutiny. No greater'service can be rendered 
to entomology, the field of discovery here proposed being as untrodden as 
it is vast. 
GENERAL EXPLANATION OF PLATES V. & VI. 
PROTHORAX. MESOTHORAX., METATHORAX. 
A&B ake Se E Prescutum internal H Prescutum 
Scutum F Scutum I Scutum 
If Parapsides (vestiges 
C Scutellum (alias) of the) 
Collare G Scutellum K_ Scutellum 
D  Postscutellum 
internal © Postscutellum inter- 
nal L_ Postscutellum 
A Epimeron R_ Epimeron M_ Epimeron 
Episternum S Episternum N Episternum 
T Parapteron O Parapteron 
U Sternum Q Sternum P Sternum 
a Squamula, Lat. 6 Socket of under wing 
é Clavicula, Chab. & Funiculus, Kird, 
y Stigma a Stigina 
8 Socketofupper wing yz Trochlea, Kirb. 
V’ Middle leg 6 Articulation of abdomen 
oa Sockets of posterior thighs 
V_ Posterior leg 
Z% Antefurca, Kirb. Y Medifurca, Kirb. W Postfurca, Kirb. 
X Part of abdomen 
