WILSON, PARASITIC COPEPODS FROM JAPAN. 3 



can be seen from fig. 3. Each is composed of about 30 over- 

 lapping chitin disks or plates; those at the base are some- 

 what smaller than those in the center, while those at the 

 tip diminish rapidly in size until the last ones are reduced 

 to mere döts. Each disk is more or less elliptical in outline, 

 and those at the base have a semielliptical puncture in their 

 basal half. The size of these punctures diminishes toward 

 the center of each rib, and they wholly disappear a little 

 beyond the center. 



Basal joint of the maxillipeds much larger than the 

 other three joints combined and triangulär in shape. The 

 basal plate is at the posterior angle and only covers the 

 space beneath the papillated area, not reaching to the an- 

 terior margin. On its posterior margin at the inner corner 

 is a large sharp spine and just outside of it another smaller 

 one. The remainder of the posterior margin is smooth, but 

 at the outer corner is a tiny papilla, the rudiment of the 

 third spine. The papillated area is abruptly raised from the 

 surface of the basal joint and resembles a piece of thick 

 felt fastened to the joint. The same is true of the areas at 

 the distal ends of the basal and second joints. These areas 

 are armed with spines and hairs, so small as to be almost 

 invisible. 



The anterior legs have large swimming flagellae, the 

 other three pairs have none. The basal joints of the fourth 

 pair are small and have tiny lobes, without any distinct heel. 



Color (preserved material) dark yellowish brown, with 

 much lighter streaks along the grooves and ribs on the dor- 

 sal surface and around the margins of the carapace and ab- 

 domen. The ventral surface is a uniform yellowish brown, 

 considerably lighter in tint. 



Total length 19 mm. Carapace 18. 50 mm. long, 12.5 

 mm. wide. Abdomen 5 mm. long, 5 mm. wide. 



{caeciis, blind, the eyes being invisible from the exteriör) 



Remarks. So far as is known this is the first species 

 of the genus in which the eyes are wholly invisible in both 

 dorsal and ventral views. This fact, together with the pe- 

 culiar structure of the supporting rods in the sucking disks 

 and of the maxillipeds, are the distinguishing characters of 

 the species. It is worthy of note that the only species thus 



