166 Prof. J. Wood-Mason's Morphological Notes 



Fig. 8. 



St 



m 



m 



Fig. 8. Machilis maritlma. The sternum with appendages of the ninth 

 abdominal somite in the female : st, sternum ; ^7, the coalesced 

 basal joints (protopodite) of one of the limbs, supporting, as in 

 the preceding somite, two branches, a, the exopodite, and b, the 

 endopodite, modified so as to form the long, jointed, and setulose 

 posterior elements of the ovipositor and articulated to the base of 

 the protopodite on the upper (dorsal) side of this, which is pro- 

 duced into a large opcrculiform plate that meets its fellow in a 

 straight suture in the middle line and carries at its extremity 

 an exopodite. In female Blaitulce, the great boat-shaped 

 seventh sternum does duty for the opcrculiform productions 

 of the exopoditic portions of the protopoditcs of both the 

 genital somites in Machllls. 



