Il8 PATTEN AND REDENBAUGH. [Vol. XVI. 



from the anterior side of the coxopodite and inserted upon the 

 outer proximal margin of the basipodite. 



The third joint, or ischiopodite {J-isc), is moved by a more 

 complicated set of muscles. A large flexor muscle (/.-^) arises 

 from the posterior side of the basipodite, and is inserted upon 

 the inner proximal margin of the ischiopodite. Another large 

 muscle (/.•^), arising from the anterior side of the basipodite, is 

 inserted upon a chitinous infolding of the arthroidal membrane 

 {apo.) on the median side of the appendage between the ischi- 

 opodite and the mero-carpopodite. This muscle acts as a flexor 

 of the mero-carpopodite, and also as an extensor of the ischi- 

 opodite. Three small muscles {e.^), arising from the outer side 

 of the ischiopodite, and inserted upon the outer margin of 

 the distal portion of the basipodite, act as extensors of the 

 ischiopodite. 



Besides the large flexor of the mero-carpopodite, above men- 

 tioned, a pair of small flexors (/.^) of the same joint arise from 

 the outer side of the ischiopodite, and are inserted upon the 

 inner margin of the proximal portion of the mero-carpopodite, 

 A pair of slender muscles (^.^) arising from the outer side of 

 the ischiopodite, near the distal end, and inserted upon the 

 inner margin of the proximal portion of the propodite, act as 

 extensors of the mero-carpopodite, and also as flexors of the 

 propodite. 



Another pair of flexors (/.-') of the propodite arise from the 

 outer side of the mero-carpopodite, and are inserted upon the 

 inner proximal margin of the propodite. The extensors {e.^) of 

 the propodite are a pair of muscles arising from the outer side 

 of the mero-carpopodite, and inserted upon the outer proximal 

 margin of the propodite. The propodite is capable of move- 

 ment upon the mero-carpopodite in any direction. Movement 

 in an anterior direction is effected by the coordinate contraction 

 of the anterior extensors and flexors, and movement in a pos- 

 terior direction, by contraction of the posterior extensors and 

 flexors. 



The dactylopodite {6-dac.) is moved by a large flexor {/}) 

 arising from the anterior, inner, and outer sides of the propodite, 

 and inserted on the anterior proximal margin of the dactylopo- 



