I'.il! A finals Eiitouwloii^ical Society oj America [\'oll III. 



the segment, behind the thoracic mass, as a whole, as being the 

 first segment. The first segment of the abdomen, counted in 

 this \va\', is attached at the ventral side of the posterior end of 

 the median segment. It is straight and nearly twice as long as 

 the second segment, just above its attachment to the median 

 segment and below the dorsal portion of the posterior carina 

 is a small but prominent muscle or funiculus, which is attached 

 to the anterior dorsal ])ortion of the ventral plate. A little in 

 front of the middle of the segment, on each side, is an oval 

 stigma, and situated about two-thirds the distance from the 

 stigma to the posterior end of the thorax is an elliptical opening 

 which, in some cases, apparently extends clear through the seg- 

 ment from side to side. On closer examination one will readily 

 detect a thin membrane, stretched across this opening about 

 in the middle of the body, separating it completely into right 

 and left halves. 



This opening is formed where the dor.sal plate bends upward, 

 and api)arently leaves the ventral plate, only the thin membrane, 

 already referred to, forming a connection between the two. 

 It then turns downward and becomes closely connected with the 

 ventral plate, again extending as narrow bands along the upper 

 margins of the same plate nearly to the median segment. 

 Viewed from above, the dorsal plate appears to divide just 

 behind the funiculus, and extends as arms to the median seg- 

 ment, forming the lateral portions already described. 



The ventral plate of the sixth segment is most jirominent. 

 From this portion of the sixth segment is ]3rotruded the ovi- 

 positor, and its palpi or feelers, which are hairy, except their 

 basal portions which are concealed by the remaining segments. 

 The ovipositor and feelers extend quite a distance beyond the 

 extremity of the abdomen. On the eighth segment, a ])air of 

 cerci are situated at its extreme posterior margin, and approxi- 

 mately half way between the ventral and dorsal portions of this 

 l)late. 



In the female the stigmata of the second and third segments 

 are well in front of the middle, while the remainder are closer 

 to the anterior margin, and none are perceptible on the last 

 two segments. In the male the stigmata approach the anterior 

 margins of the segments more and more passing backward, 

 but they do not come close to it. On the seventh and eighth 

 they appear to be absent. 



