Marshall—Arrhenuri From Washington and Alaska. 215 
Arrhenurus acerfonnis nov. spec. 
PL VIII, fig. 8, 9, 13 
At Chitna, Alaska, about one hundred and thirty-five miles in¬ 
land on the Copper River & Northwestern Railway from the sea¬ 
port town of Cordova, a number of small ponds were examined. 
Only one of these yielded any Arrhenuri; this was a pond in the 
mountains, surrounded by the forest, and called Lost Lake. It is 
a circular body of water, perhaps a half mile in circumference, 
apparently shallow, with a border of yellow water lilies among 
sunken logs at one place. This pond is said to be seven hundred 
and fifty feet above the town, some two miles away. Only two 
Arrhenuri were found, both females, but representing two species. 
As this genus is usually very common in the quiet waters of low¬ 
lands and plains, much interest attaches to the finding of these 
specimens at this elevation. It is hoped that the males may be dis¬ 
covered in future collections by the aid of the accompanying fig*^ 
ures, since the palpi are alike in the two sexes. 
A. acerformis, female, is oval in form, 1.45 mm. long and 1.1 mm. 
across at the widest part. The color is dull olive green. The 
epimera of the first pair end in rather sharp points. The genital 
area is some distance from the fourth pair of epimera; in form, the 
wing-like areas bear a fanciful resemblance to the twin seeds of 
certain maples, and this has suggested the specific name. 
Arrhenunis hirsutus nov. spec. 
PI. YIII, fig. 10-12 
This is a smaller species, found with the preceding species, and 
represented also by but one individual, a female. It is pyriform 
in shape, 1.2 mm. long and 0.96 mm. in the widest part. The gen¬ 
ital area is close to the last epimera, and the wing-like expansions 
are short and inclined from the plates guarding the opening. The 
palpi have several long stout hairs or bristles on the second joint, 
a character which has suggested the name of the species. The color 
is the usual dull olive green. 
