io8 



Parasitic Arthropoda 



these seasons they are frequently to be found upon the windows of 

 dwellings, where they are often mistaken for mosquitoes. 



The larvae are worm-like, but vary somewhat in form in the differ- 

 ent genera. Most of them are aquatic, but a few live in the earth, in 

 manure, decaying wood, under bark, or in the sap of trees, especially 

 in the sap which collects in wounds. 



Of the many species of Chironomidae, (over eight hundred known) , 

 the vast majority are inoffensive. The sub-family Ceratopogoninae, 

 however, forms an exception, for some of the members of this group , 



77. Culicoides guttipennis; (a) adult, (x 15); (&) head of same; (c} larva; 

 (d) head; (e) pupa. After Pratt. 



known as sandflies, or punkies, suck blood and are particularly trouble- 

 some in the mountains, along streams, and at the seashore. Most of 

 these have been classed under the genus Ceratopogon, but the group 

 has been broken up into a number of genera and Ceratopogon, in the 

 strict sense, is not known to contain any species which sucks the blood 

 of vertebrates. 



The Ceratopogoninae The Ceratopogoninae are among the smallest 

 of the Diptera, many of them being hardly a millimeter long and some 

 not even so large. They are Chironomidas in which the thorax is not 

 prolonged over the head. The antennae are filiform with fourteen 

 (rarely thirteen) segments in both sexes, those of the male being brush- 

 like. The basal segment is enlarged, the last segment never longer 



