﻿The Life History of Two Species of Ndbidae 151 



On hatching, the small, white nymphs, barely visible to the naked 

 eye, were collected from the plants by means of a camels-hair-brush 

 and placed in petri dishes, one or two in a dish. Each receptacle 

 had been cleaned and a raspberry leaf placed within. Upon the 

 leaf a drop or two of water was put, and also food in the form 

 of aphids — one large one or two small ones per nymph. Each 

 dish was numbered according to the box from which the specimens 

 were taken, and the date of hatching placed upon it. Besides this, 

 each additional dish was marked by a separate letter, date of begin- 

 ning and other data as above. There were times when many 

 nymphs had to be placed in one dish because of their great num- 

 bers. Over fifty cages were in operation at one time. 



Every day observations of each dish were taken and the dishes 

 thoroughly cleaned and supplied with a fresh leaf, water and food. 

 Two nymphs from each instar were placed in alcohol for future 

 study. One was taken as near the beginning of the instar as 

 possible, and the other as close to the end of the instar as possible. 

 Careful records were made of dates of moulting. By these methods 

 about twelve specimens were carried successfully through to the 

 adult stage. A later chart will show the mortality during this 

 time, but it must be remembered that this includes the specimens 

 preserved throughout the various instars. 



Nabis roseipennis 



N. roseipennis^ commonly known as one of the blond damsel 

 bugs, was first described by Renter in 1872. It belongs to the 

 order Hemiptera, suborder Heteroptera, family Ndbidae Costa, 

 subfamily Nabinae Renter and genus Nabis Latriele. 



Distribution 



N. roseipennis is practically transcontinental in North America, 

 occurring from British Columbia to Colorado and New Brunswick 

 to Virginia. It has been reported from the following regions north 

 of Mexico ; Northern Canada, Western Canada, Ontario, Maine, 

 New Yoi'k, New Hampshire, Massachusetts, Connecticut, Pennsyl- 

 vania, Delaware, New Jersey, District of Columbia, Ohio, Wis- 

 consin, Iowa, Nebraska, Kansas and Colorado. 



Genitalia 



For a proper understanding of some of the observations later 

 recorded, some knowledge of the genitalia and ovipositors is 

 necessary. 



In the male, the last segment of the abdomen is hollowed-out 

 at each side dorso-laterally and accommodates a clasper in each 

 concavity. The clasper in general outline is spoon-shaped, as shown 

 in Fig. 32, with the extreme ends bent slightly out of the same 

 plane. It is fastened at the smaller posterior end and extends 

 forward. A few hairs arise from this posterior portion. The 



