1030 Wisconsin Academy of Sciences, Arts, and Letters. 
valves. These axe normally spread out laterally something 
like the ribs of a fan, and doubtless aid in supporting the 
animal as it lies on the loose debris of the bottom. The full 
number is rarely found, and many specimens have lost all of 
them. At the base of this cluster of setae the shell is pro¬ 
duced into a short, blunt spine, which extends beyond the 
elevations to which the setae are attached. This apparently 
serves to stiffen the valve at this point. The posterior margin 
has a row of minute close-set spinules which do not project 
beyond its edge. 
The abdominal setae are moderately long, 2-jointed, plumose, 
and borne on distinct and widely separated papillae. The 
postabdomen is conical, bearing 9-15 small, lateral, anal 
spines, larger toward the distal end of the row. The terminal 
claws are long, finely serrate, with two long basal spines. 
The form of the antennule is between that of Latona and La- 
tonopsis , more nearly approaching the latter genus. There is 
a short, stout, straight basal part and a long flagellum united 
with it and forming a continuation of the base. The flagel¬ 
lum is covered with long, fine, straggling hairs much less 
closely set than in L. setifera. The antennules shows no angle 
at junction of base and flagellum. The latter structure is 
somewhat stouter than in Latonopsis. The olfactory setae 
are on the distal end and posterior side of the base. 
The antennae have a large, stout basal joint, like that of 
L. setifera. It bears a stout, conical spine or thorn at the 
base and a similar structure on the outer side of the distal 
end. It has also a stout spine and a slender, plumose sense- 
hair on the distal end between the insertion of the rami. The 
dorsal ramus is 2-jointed and has a lateral setigerous expan¬ 
sion of the proximal joint; but this is much smaller than that 
of L. setifera, bearing only 5-6 setae. From this character 
comes the specific name, parviremis. The setae are ~ 8 ^ ■ 
The ventral ramus has a long seta on the second joint and one 
of the 4 terminal setae is much larger than the others. The 
inequality is greater than in L. setifera, but not equal to that 
of Latonopsis or Pseudosida. American specimens of L. seti- 
