THE ANNALS 



AND 



MAGAZINE OF NATURAL HlSTOliY. 



[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 *. 



It was chiefly in consequence of my work upon the Crustacea 

 belonging to '' Dijmphna-Togtet's zoolog.-botan. UJbytte " 

 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 tlie 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 An!!eip:er,' xvi. Jahrg., no3. 420 

 and 421 (May 29 and June 12, 1SJ)3), pp. 193-198 and 201-212. 



Ann. & Mag. N. Hist. Ser. 6. l^ol. xii. 32 



