92 IOWA STUDIES IN NATURAL HISTORY 
vial containing the specimen selected, for this reason, as the holotype. 
Hand thick and stout, compressed but rounded above and below; both 
fingers short and stout; immovable finger the longer, and at first glance 
appearing to be furnished with a tooth at or just before the middle of 
its length, on closer inspection it is seen to be but indicated by a dis- 
colored or corneous area or interspace between the tip of the finger and 
the apparent tooth; the smooth palm has on its inner face a thin line of 
hair tufts on a level with the middle of the base of the movable finger 
extending back about to its posterior margin, and on the outer face with 
another more thickly set row of hairs extending obliquely from about the 
same level proximally, nearly to the base of the sinus between the fingers, 
where it curves abruptly downward to meet the lower margin of the palm, 
lower margin of hand with fringe of long hair for the greater part of 
its length; upper and lower margins of carpus unarmed, there is how- 
ever a single, blunt tooth on its inner face near but below the upper 
distal angle, in line with the line of hair on the inner face of the palm; 
merus proximally broken off, below with fringe of long hair just within 
or on the medial side of the row of tiny, inconspicuous denticulations 
marking the inferior margin of the joint. The only legs attached to the 
body are those of the fifth pair of which the left leg is small and 
evidently regenerated; the right leg is imperfectly subchelate, propodus 
thick, hirsute, little shorter than carpus, about equal to the merus in 
length, dactyl, long, curved, tapering to a nearly acute tip, about twice 
as long as produced infero-distal angle of propodus constituting the fixed 
finger, and extending for half its length beyond it when folded against 
the distal margin of the propodus. Of the legs loose in the vial with 
the type specimen, one which may be taken as the second left leg has 
the merus subequal to or slightly shorter than the ischium, about one- 
third longer than the carpus and about as long as the propodus; propodus 
compressed with fringe of long hair on upper and lower margin, the 
stout three angled dactyl is about one-third as long as propodus. 
The terminal portion of the abdomen of U. rugosa as described by 
Lockington applies equally well to the species before us. As he has it 
(op. cit., p. 301), ‘‘ Posterior margin of fourth abdominal segment beset 
with short stiff hairs; the three posterior segments [inclusive of telson] 
and the lateral caudal appendages complexly wrinkled above, the rugae 
smooth. Terminal segment [telson] broader than long, distal margin 
longer than proximal; caudal processes large, filling up the space between 
the terminal and fifth segments.’’ In our species the first three abdo- 
minal segments are dorsally smooth, as is likewise the fourth which car- 
ries a line of hair across its anterior third and a thick fringe, or brush 
of hair along its entire posterior margin sharply setting it off from the 
fifth somite; fifth and sixth somites ‘‘complexly’’ but symmetrically 
‘“wrinkled’’ telson and uropods with smooth rugae some of which bifur- 
cate or are incomplete; proximal half of fifth somite and distal moiety 
of telson and of uropods longitudinally concave or transversely troughed 
for their entire, respective widths; tail fan when fully expanded form- 
