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Superfamily Cyrtoidea 



I have provisionally placed in this superfamily two families, 

 Cyrtidae and Nemestrinidae. I have seen the young larva and the pupa 

 of Cyrtidae, but the other family is quite unknown to me. I have 

 some doubts as to the propriety of linking these families together but 

 can not suggest a better affiliation for Nemestrinidae, though the 

 imagines are more dissimilar than is the rule in most superfamilies 

 in Brachycera. 



The larva of one species of Nemestrinidae has been described by 

 Brauer. The species is recorded as being an internal parasite of cole- 

 opterous larvae. 



Family CYRTIDAE 



Larva. — First-stage larva very active, armed on body with numer- 

 ous spinose plates and single spines and with 2 long apical bristles, 

 the latter serving as a means of propulsion in making the leaps which 

 the larvae take before entering their hosts. On finding a location in 

 the host the appearance of the larva changes radically, and it becomes 

 maggot-like and very sluggish. The head is very small and almost 

 entirely retracted. The prothoracic spiracles are minute, the anal 

 pair much larger, slightly elevated, distinctly separated, and situated 

 on the apical segment. The segmentation is rather indistinct, but the 

 thoracic segments are clearly differentiated from the abdomen, being 

 much more slender. The locomotor organs consist of a pair of slight 

 elevations on segments 5-1 1 which are armed with minute spinules. 



Pupa (PI. LIII, Fig. i). — Distinguished from every other family 

 by the very large thorax, which exceeds the abdomen in length, by the 

 short, stout abdomen, with its apex slightly recurved ventrally, by the 

 4 or 5 pairs of lateral abdominal spiracles, and by the entire absence 

 of bristles or thorns on all parts of the body. 



Imago. — Distinguished by the very small head, globose thorax, 

 and very short, stout abdomen. 



HABITS OF LARVAE 



The larvae are internal parasites of spiders, passing the winter 

 within the body of their hosts. 



HABITS OF IMAGINES 



The imagines are commonly rare, but occasionally they may be 

 taken in considerable numbers flying round or settling upon dead 



