NATHAN BANKS. 29 



toward the cubitus at connecting veinlet ; in hindwiugs the median 

 usually forks plainly beyond forking of radial sector; small species. 



Syinphcrobiiis. 



Outer cross-vein lets present in hindwings; more than four veinlets in outer 



gradate series in forewings; usually three oi- four radial sectors. . • -4. 



4. A cross-veinlet connecting first radial sector to median some distance out on 



the former; often four radical sectors; the median is rarely bent 

 toward the cubitus at connecting veinlet; in hindwings the first radial 

 sector forks as far out as forking of median ; larger sjiecies. 



Borioiiiyia. 



The cross-vein from median to radius is before or at origin of radial sector, 



never out upon it; three, rarely four, radial sectors; the median is 



more or less bent toward cubitus at connecting veinlet; in hindwings 



the median is forked farther out than fork of first radial sector. 



Heinerobiiis. 



5. But one radial sector, and but one series of gradate veinlets Pseclra. 



Several radial sectors, and two series of gradate veinlets Microimis. 



HEilIEROBIUS Linn. 



Autennje moniliforin ; wings entire; subcosta ending in margin ; 

 costal area quite broad at base; with a recurrent nervure ; costal 

 cross-veins branched ; two series of gradate veinlets in both pairs of 

 wings, the outer in forewings of more than four veinlets ; no cross- 

 vein connecting first radial sector to median ; three or four radial 

 sectors; the median is bent more or less toward the cubitus at con- 

 necting veinlet; in hindwings the median is forked farther out than 

 fork of first radial sector. 



Type. — H. hximuli Linn. 



The type of Mucropalpas Rambur is M. lutescens Rambur (nee. 

 Fabricius), and is the same as H. humuli. 



The Hemerobius of Linne covered everything in this family and 

 the Chrysopidse, as well as other forms; gradually it has been re- 

 stricted, and I have now divided in into three genera, retaining the 

 name for the best known section. The custom of years has fixed 

 the name, although several earlier authors used it for Chrysopa. In 

 correspondence with Prof. Klapalek, who has kindly furnished me 

 with many European species, I find that this division of the genus 

 will apply to the European species as follows : Hemerobius (s. str.) ; 

 humuli, viicans, atr'ifrons, nitidulus, stigma, limbatellus, lutescens, 

 orotypus ; JBoriomyia : concinnus, 4--f(^sciatus, subnebulosus, nervosus ; 

 Sympherobius : eleyans, parvulus, inconsjncuus. 



TRANS. AM. ENT. SOC. XXXII. DECEMBER, 190."). 



