148 



PATTEN AND REDENBAUGH. 



[Vol. XVI. 



endo. 



■Ic.n. 



Fig. 12. — Diagram showing the muscles and distribution of the nerves in the sixth leg of Limulus, 

 from the anterior side {% natural size). 



i-cox., coxopodite, or first joint ; 2-bas., basipodite, or second joint ; 3-isc., ischiopodite, or 



third joint ; 4- \ '■"■^■' fused carpopodite'and meropodite, or fourth joint ; 5-pro., propodite, or 



fifth joint ; 6-^i'rc., dactylopodite, or sixth joint ; apo., apodenie ; br., brain ; cc, cross-commis- 

 sure ; endo., endocranium ; Jlab., flabellum ; h.c, haemal side of carapace; lit., heart; int., 

 intestine; inan., mandible; />.s., pericardial sinus. 



Muscles: 6 a and '^ plastro-coxal muscles inserted upon anterior side of entocoxite ; 

 6c and '', tergo-coxal muscles inserted upon anterior side of entocoxite; e.^-"!, extensors of 

 second to seventh joints \/.^''', flexors of second to seventh joints; i.m., inter-tergal muscle. 



Nervhs : a.e.n., anterior ento-coxal nerve ; e.p.ti., external pedal nerve; /;., haemal branch 

 of integumentary nerve ; h.n.^, haemal nerve; i.n.^, intestinal nerve; in.?!.^, integumentary 

 branch of haemal nerve; i.p.n., internal pedal nerve; l.c.n., lateral cardiac nerve; in.c.n. 

 median cardiac nerve; tn.e.n., median ento-coxal nerve or flabellar nerve; ;«.«., mandibular 

 nerve; «., neural branch of integumentary nerve; n.n.^, neural nerve; /., pericardium; 

 p.e.71., posterior ento-coxal nerve ; s.c.nf', segmental cardiac nerves. 



