THE ANNALS 
MAGAZINE OF NATURAL HISTORY. 
[SIXTH SERIES.] 
No. 72. DECEMBER 1893. 
LX.—A Contribution to the Morphology of the Limbs and , 
Mouth-parts of Crustaceans and Insects. By Dr. H. J. 
HANSEN, of Copenhagen *. 
Ir was chiefly in consequence of my work upon the Crustacea 
belonging to “ Dijmphna-Togtet’s zoolog.-botan. Udbytte ” 
of 1884-1885 that I was led to the study of the morphology 
of the skeleton of this class of animals. Since then I have 
more than once devoted some time to similar morphological 
studies of most of the orders of all four classes of the Arthro- 
poda, and it is my intention to publish a more extensive 
memoir dealing with a series of such questions in the case of 
the Insects, Myriopods, and Crustaceans. Many of the 
figures are already prepared; other circumstances have, how- 
ever, induced me to resolve no longer to postpone a provi- 
sional publication of the greater portion of the most important 
of my results. 
I may be permitted to mention that the views to be detailed 
in the following pages have been developed in the course of 
eight years as a result of the periodical investigations to which 
I have alluded; that I have been able to devote considerable 
time to repeated consideration, to the acquisition of a good 
supply of material, and to the practice of the necessary dis- 
section, which is often very difficult owing to the small size 
of the majority of the objects, in order to make myself familiar 
* Translated from the ‘ Zoologischer Anzeiger, xvi. Jahrg., nos. 420 
and 421 (May 29 and June 12, 1893), pp. 193-198 and 201-212. 
Ann. & Mag. N. Hist. Ser. 6. Vol. xii. 32 
