hungerford: aquatic hemiptera. 155 



more convex than with the true R. quadridentata Stal., the cheeks sen- 

 sibly more elongated and more prominent in front of the eyes, subparallel, 

 a little attenuated in front, but not divergent at the summit, better 

 applied against the tylus, M^hich surpasses it, also very sensibly in front, 

 w^hich gives to the anterior part of the head a form a little more elongate 

 in front of the eyes. 



"Pronotum very visivly narrow^ed in the middle, enlarging insensibly in 

 the rear and in front. This character permits one to distinguish quite 

 easily this form from the true R. quadridentata Stal., with which the 

 median constriction of the pronotum is a great deal less marked (assuse) 

 and the anterior part more cylindrical. 



"The majority of the examples of this species have the double tooth at 

 the extremity of the anterior femur, which has confused it with the 

 true R. quadridentata Stal.; but this double tooth is often very attenu- 

 ated and sometimes even altogether atrophied. I have distinguished 

 this latter example under the name of R. americamis var. edentula. It is 

 represented in my collection by two single female examples, one from 

 Pennsylvania, and the other from Texas." 



Bueno, in his "Three Ranatras of N. E. U. S.," states that the legs of 

 R. quadridentata are not unduly long, the tarsal claws of the third pair 

 barely going beyond the middle of the air tubes, and the extremity of the 

 femora going but little beyond the anterior margin of the penultimate 

 abdominal segment. The eyes moderately large and the prothorax more 

 stoutly built and bisulcate beneath. 



Ranatra brevicollis Montd. 1910. 



Montd. Bui. Soc. Sco. Bucarest, XVIII, p. 184. 



"It is indeed regrettable that I have described this new form from one 

 unfortunately unique specimen, very little dissimilar, at first sight, from 

 R. quadridentata Stal., but its specific characters do not permit it to be 

 confused with the other species, fusca or quadridentata, from which it 

 differs by its anterior femora being very slightly sinuate toward their 

 extremities. It also has a single tooth before the median sinus of the 

 femur. A little more thick-set, of form less elongate than R. fusca Pall 

 de B., which would bring it closer to R. quadridentata Stal. It is sep- 

 arated as plainly from this latter form by the much shorter form of the 

 pronotum. In fact, the insect is 34 mm. long, of which length the .head 

 and pronotum have only 10 mm. The appendages of 22 mm. are sen- 

 sibly shorter than the abdomen. The intermediate and short posterior 

 femora, folded forward, scarcely surpass the head. 



"The pronotum very robust, about a third as long as the abdomen, 

 quite strongly dilated in front, and very strongly enlarged behind, does 

 not allow confusion with R. kirkaldyi T. B. It is, besides, marked by two 

 longitudinal grooves, slightly oblique on the sides, behind the anterior 

 dilation, not attaining behind the transverse grooves which limit in 

 front the posterior dilated part of the pronotum. This latter marked 

 by a longitudinal median carina disappearing behind, less emphasized 

 in front, where it traverses the transverse groove which limits the 

 posterior dilated part. 



"The legs are very slender, a little shorter proportionally than those 

 of R. quadridentata Stal.; femora reddish, marked by pale, wide, little 

 visible annulations. 



"Metasternum in a plate (metasternal plate) terminated in the middle 

 behind by a narrowed prolongation between the posterior coxse, appear- 

 ing more elevated than in R. fusca P. de B. and R. quadridentata Stal., 

 but less, however, than in R. fahricii Guer. -annulipes Stal. 



"This species, however, is distinguished from the three other known 



