HEMIPTEBA HETEBOPTERA HYDROBATID 351 



Hydrometra In tin- European Tertiarie-, (iei-mar figures two insect- .he 

 regards as immature and as belonging to llydrometra or Ilalobutes, or both, 

 and which also appear to belong to this family. Burmeister further 

 that Serres mentions a "characteristic 1 1 yilrometra " from Aix, but as a 

 comparison will shmv. he has evidently written 1 1 vdrom.' 1 ) :i tor I'loiaria. 

 and that, is quite another insect. In our own country we have a coup],- (( f 

 species from Wyoming and British Columbia belonging to an extinct ^enns, 

 Telmatrechus, described la-low, related to Hygrotrechus, found in tin- 

 North Temperate /.one of both worlds; and a species of Metrol 

 genus peculiar to eastern North America. 



TELMATRECHUS gen. nov. (reXfin, 



This genus is closely allied to Hygrotrechua Stal, and, combining as 

 it does many of the features of this genus and Limnotrechus Stal, may well 

 have been the lineal predecessor of both. The antenna; have the first joint 

 only a little longer than the second. The eyes are not at all prominent. 

 The thorax is relatively shorter than in Hygrotrechus. The legs are MTV 

 long, the tibia- of each pair of legs about as long as the femora of the same 

 legs, an equality which I have not found in any other genera of Ilvdro- 

 batid.-e ; in the fore legs the equality is perfect; in the middle legs the 

 tibia- are slightly longer, in the hind legs slightly shorter, than the femora ; 

 the hind femora are .slightly longer than the middle pair; so far as can h- 

 told from the imperfect remains the tarsi of the middle and hind legs are 

 very much shorter than, not a half or probably a third tin- length of, their 

 respective tibia-. The posterior lateral edges of the sixth abdominal - 

 ment are produced to a tooth precisely as in Limnotrechus. 



Two species are found in the \ve>tern Tertiaries. 



Tabl> nf tin < Titniiitri'fliuH. 



I'M uly -.tun I, with ilium*! rc^nl :n 1\ t:i|iri iiiL,' ill"! ...... -n ...................................... 1. 7". 



l!i"l\ ilnnlrr, with nearly eqnol abdomen, tapering distinctly milv at the extremity.. .2. T. paral 



1. Ti:i.MA'l i;i.( III s >TALI. 



PI. '_', \\z. 11, 11.'. 



irii!i>;>tr,,-in,.i ../;,/! Sruii.i.. KY|>. l'n.-r. Cn.i. Surv. Can .i-:: i-ii; IK 



The thorax seems to lie shorter than in 1 1 v^rotrechiis, \\ith the 1- 

 of the prosternum more visibly marked tVom above; the eyes dp not ap- 

 jiear to In- so prominent, and the first antennal joint would M-em, from the 



