STUDIES ON LIMULUS. 



II. THE NERVOUS SYSTEM OF LIMULUS POLYPHEMUS, WITH 

 OBSERVATIONS UPON THE GENERAL ANATOMY. 



WILLIAM PATTEN and WILLIAM A. REDENBAUGH. 



Dartmouth College, Hanover, N. H. 



CONTENTS. 



PACK 



Introduction 98 



1 . Historical. 



Researches of Van der Hoeven, Gegenbaur, Dohm, Lockwood, Packard, 

 Owen, Milne-Edwards, Lankester, Benham, Patten, Viallanes, and Hyde ... 102 



2. Methods. 



Maceration in water and weak alcohol previous to dissection; sectioning 



and staining 103 



Gold Chloride Method. 104 



Methylen Blue Method 104 



I. Preliminary Description of the Anatomy of Limulus. 



I. External Form. 



Cephalothorax : eyes, olfactory organs, appendages, and nephridial openings 105 



Abdomen: appendages, anus 106 



Caudal spine 106 



Etttapophyses 106 



Tendinous Stigmata 106 



Appendages 106 



Chelicerae 107 



Thoracic appendages from the second to the fifth ; modification of chelae 

 of second pair in the male ; entocoxites, sensory knobs, mandibles, inner 



mandibles, or " epicoxites," apodeme of third joint 107 



Sixth pair of appendages ; flabellum, modification of distal joints for 



burrowing 108 



Chilaria 108 



Operculum ; genital papillae 108 



Gills ; gill book 109 



91 



