BULLETIN 



UsTSTITTJTIE. 



VOL. 21. SALEM: JAN., FEB., MARCH, 1889. Nos. 1-2-3. 



THE DEVELOPMENT OF CRANGON VULGARIS. 

 THIRD PAPER, 1 WITH PLATES I, II, III. 



BY J. S. KINGSLEY, SC.D. 



THE ALIMENTARY CANAL AND ITS APPENDAGES. 



IN the preceding account(Vol. xvm, pp. 109-138, pi. i, 

 figs. 7, 8 and 9) may be found a description of the process 

 of gastrulation in Crangon, together with a summary of the 

 then existing literature of the development of the germ 

 layers in the Arthropods. To this account I would here 

 add a few supplementary remarks, bringing the subject 

 down to the date of writing and also correcting my own 

 observations in the light of my later studies. 



Since the article referred to was in type, several papers 

 on Arthropod development have appeared, which have a 

 bearing upon the points discussed. First is that of Morin 

 ('87), on the development of spiders belonging to the 



1 Continued from the Bulletin of the Essex Institute, Vol. xvm, 

 pages 99-153. 1886. Published May, 1887. The numbering of the 

 figures on the accompanying plates is consecutive with that of the 

 preceding part of this series. 



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