PARASITIC COPEPODS— WILSON. 



333 



family. There is a tendency to degeneration in the swimming legs 

 similar to that shown in the PandariniB, but wliile it was there con- 

 fined to the female sex only it here extends to both sexes, and may 

 even include both the third and fourth pairs of legs in the male 

 {Orthagoriscicola males) . 



ONTOGENY. 



The life histories in tliis subfamily are almost the same as in the 

 Cahginffi and Euryphorinas. The differentiation between the two 

 must be sought cliiefly in the habits and sexual characters, as already 

 stated. The number and size of the eggs and the changes during 

 their development are similar to those given in the preceding sub- 

 families. From eight to ten weeks are required for development, and 



Fig. 4.— a newly hatched nauplius of Pandarus sinitatus. 



all the eggs in the strings of any given female hatch at practically the 

 same time. The issuing nauplius is almost an exact counterpart of 

 that seen in the Euryphorinse ; its body has the outline of an elon- 

 gated ellipse, is well rounded anteriorly, but is somewhat contracted 

 posteriorly through the bases of the balancers (fig. 4). The eye spot 

 is far forward and not prominent. The three pairs of appendages are 

 of the usual pattern and arrangement. The anterior part of the 

 body is transparent, and inside of it can be plainly seen the muscles 

 which move the appendages. The balancers are very long, cylindrical, 

 and narrow acuminate ; they stand out nearly at right angles to the 

 body axis and are curved slightly forward. The central portion of 

 the posterior half of the body is filled with opaque yolk granules, 

 leaving a narrow transparent margin around the edge. These granules 

 are colored a uniform and very pale brownish-yellow, and there are no 



