HUNGERFORD: AQUATIC HEMIPTERA. 51 
The Nymph. 
In the last nymphal instar the wing pads reach to the base of the 
abdomen. The lateral.margins of the prothorax are flattened but not 
“buckled” or constricted as in adult. The hind tarsi are single segmented. 
Ocelli are present! In Mononyx fuscipes, Champion says the ocelli are 
absent in the nymph. This is the usual case. 
Genus MONONYX Guer. 
So little is recorded in regard to the biology of the species that some 
one should rear it. It is predatory, as was long ago recorded. 
Champion says that the adult has only one claw on its fore tarsi, the 
nymph of M. fuscipes has two long claws. The segments of the inter- 
mediate and hind tarsi are fused into one, and the third and fourth an- 
tennal joints are connate. The ocelli are absent. 
Habitat. ‘These insects live in muddy places on the banks of ponds 
and streams and are usually coated with an earthy incrustation, which 
cannot be easily removed.” 
Family OCHTERIDZ Kirk. 1906. 
A. TAXONOMY OF THE OCHTERIDZ. 
Family Characteristics. Shore bugs with characters intermediate be- 
tween those of Saldidx and those of Gelastocoride. The general appear- 
ance is also intermediate, resembling some of the Saldids, perhaps more 
than the toad bugs. The antenne are four segmented, shorter than the 
head, but exposed. The eyes are prominent, two ocelli present. Fore 
femora slightly if at all fitted for grasping. Rostrum is long, like that 
of.the Saldids, reaching the hind coxe. The first and second segments 
are short, third, very long and slender. Tarsi are given by Parshley as 
two-segmented behind, with a question mark after the statement “front 
and intermediate tarsi one-segmented.”” We have but two specimens in the 
Snow collections at University of Kansas. The middle tarsi appear two 
segmented under binocular. Professor Barber’s drawing of his Ochterus 
banski shows three segments in hind tarsi and two in each of the others. 
Historical Review. There is but one genus in the family. Ochterus 
Latr. 1807. He suggested the name Pelogonus for this genus two years 
later because he believed Ochterus was preoccupied. It is under the name 
Pelogonus that Uhler mentions these insects. The genus is sufficiently 
characterized by the family description. A more nearly complete de- 
scription can be found in Amyot & Serville, page 407. 
KEY TO SPECIES OF OCHTERUS. 
1 (After Barber.) 
A. Clavus entirely yellow. O. flaviclavus Barber. 
AA. Clavus concolorous. 
B. Entire lateral pronotal margins broadly pale. 
O. banksi Barber. 
BB. Lateral pronotal margins, with only a pale spot anteriorly. 
O. americanus Uhl. 
