Hungerford: Nepid.e in America. 439 



TECHNIQUE USED. 



The antennee arc often covered with debris that should be re- 

 moved. If the antennae are still difficult to see, the specimen may be 

 relaxed and antennae moved into view with dissecting needle. The 

 genital capsule of the male lies in the last abdominal segment, en- 

 tirely hidden. To examine this, relax the specimen in a moist cham- 

 ber, then holding the specimen on its right side in the left hand, 

 lower the operculum with a dissecting needle and draw out the 

 capsule. A needle with just the very tip turned at right angle is 

 best to use. It can be inserted alongside the capsule, turned so 

 that the hook is against the capsule, and slowly withdrawn, bringing 

 with it the desired organ. If the respiratory filaments start to come 

 also, loosen the capsule from them by inserting the needle between 

 capsule and filaments on each side. The capsule may be removed 

 entirely and mounted upon a card below the insect, or simply drawn 

 into view. The insects are not in the least damaged, and the male 

 capsules may be taken out and operculum pressed back into place 

 by a careful person without it being detected by the closest exam- 

 ination of the exterior. 



KEY TO THE SPECIES. 



A. Antennae simple, distal end of the penultimate segment without lateral 

 prolongation. Front femora broad and stout and not narrowed near 

 middle. 



B. Front femora without apical tooth or marked sinuosity. 



R. kirkaldyi Bueno. 

 BB. Front femora with apical tooth or a marked sinuosity. 



R. kirkaldyi Bueno. 

 var. hoffmanni, new. 



AA. Antennae with distal end of penultimate segment with a lateral pro- 

 longation. Front femora somewhat narrowed in their middle section. 



B. The lateral prolongation of the penultimate segment of- antennae 

 not greater than one-half of the length of the ultimate segment. 

 Front femora very slender and without apical tooth. 



C. Prosternum with a single wide, deep longitudinal trough. Eyes 

 veiy prominent. . R. buenoi, sp. new. 



{=R. jusca Bueno.) 

 CC. Prosternum without the deep trough, but possessing two 

 longitudinal depressed lines characteristic of most species of 

 Ranatra. R. nigra H. S. 



{=R. protensa Montd.) 

 BB. The lateral prolongation of the penultimate segment of antennae 

 greater than one-half the length of the ultimate segment. 

 C. Sides of body (connexivum) embracing the operculum of the 

 genital segment at its extremity (see fig. 11, pi. XLV), 



R. annulipes Stal. 

 {=:R. fabricii Gu^r.) 



