130 THE CEAYFISH 



spermatozoa to the female. The protopodite 

 and exopodite resemble those of XVIII., but the 

 large proximal joint of the endopodite is pro- 

 duced distaUy on its inner side into a short 

 plate, rolled longitudinally upon itself to form 

 an imperfect tube : the remainder of the endo- 

 podite is a small jointed rod as in XVIII. 



XIV. In the female this is reduced or absent. 



In the male it is modified for the same pur- 

 pose as XV. It is an unjointed rod, the distal 

 portion of which is flattened and rolled upon 

 itself to form an imperfect tube. It is probably 

 formed of the protopodite and endopodite fused 

 together. 



2. The thoracic appendages, of which there are eight pairs, 

 fall readily into two groups : a posterior group of 

 five pairs of large appendages, XIII. to IX., used for 

 walking and prehension, and devoid of esopodites ; 

 and an anterior group of three pairs of maxillipedes 

 or foot-jaws, VIII. to VI., which possess both exopo- 

 dites and endopodites, and aid in passing food to the 

 mouth. 



XII. The last but one of the thoracic legs may be 

 taken as a type of the series. 



i. The protopodite consists of two joints, of which 

 the first, or coxopodite, is short and broad, 

 and bears a large gill and a tuft of long fine 

 hairs, the 'coxopoditic setaB.' The second 

 joint or basipodite is much smaller, and bears 

 the endopodite. 



ii. The endopodite consists of five joints named as 

 follows, beginning at the proximal end : — 

 ischiopodite, meropodite, earpopodite, propo- 

 dite, and dactylopodite. Of these the mero- 

 podite and the propodite are the longest, and 

 the dactylopodite is clawlike. 



