354 HEMIPTERA-HETEROPTERA. 
thus being fully exposed). In the form of the metasternum &. fusca approaches 
R. (Amphischizops) compressicollis, Mont., from Venezuela. 
2. Ranatra quadridentata. 
Ranatra quadridentata, Stal, Ofv. Vet.-Ak. Férh. xviii. p. 204 (1861)*; Uhler, Bull. U.S. Geol. 
& Geogr. Surv. i. p. 338°; in Kingsley’s Stand. Nat. Hist. ii. p. 255°; Proc. Calif. Acad. 
Sci. (2) iv. p. 292%. 
Hab. Norta America, Upper? and Lower California 4, Illinois?, Arizona?.—MExico? 
(Mus. Holm.), Sonora 3. 
Unknown to me. 
Fam, NAUCORIDZ. 
This is the last family dealt with by Stal in the fifth part of his ‘ Enumeratio Hemi- 
pterorum,’ published in 1876. During recent years very many American species have 
been described by Montandon, chiefly from material contained in the Stockholm, Vienna, 
Paris, and Hamburg Museums, as well as from a certain number in his own collection. 
We possess, unfortunately, very few Naucoride from Central America, nine species 
only being represented in our collection. Various types, however, have been lent us, 
so that we are enabled to figure most of the known forms. The sexual characters are 
important in some cases, as in Pelocoris, these insects having the terminal abdominal 
segments very differently formed in the two sexes. None of the Naucoride, so far as 
I am aware, carry their eggs about on their backs, a common habit with many of the 
Belostomide. Some of the species live in stagnant, others in running water. 
Subfam. CRYPHOCRICIN A. 
CRY PHOCRICUS. 
Cryphocricos, Signoret, Rev. et Mag. Zool. 1850, p. 290. 
Cryptocricus, Stal, Enum. Hemipt. v. pp. 141, 143; Montandon, Verh. zool.-bot. Ges. Wien, 1897, 
pp. 6, 7. 
The type of this genus, C. barozzi, Sign., from Brazil *, is a brachypterous insect, 
with very peculiarly formed abdominal segments in the male. C. macrocephalus, if 
correctly identified by me, differs in many respects, and should probably form the type 
of a new genus, when the male is discovered. In the form of the legs it approaches 
the Belostomide. 
* Montandon, who has redescribed it (Verh. zool.-bot. Ges. Wien, 1897, p. 7), gives “Chili” as the 
locality. 
