Vol. xxvi] BirroMOLocicAL news S9 



Labram with hinge halfwmy between fir*t and tcoood pain of Icfk 

 Mcotal MCae vartaUc in number, tuoally foor on ooc tide, two oa the 

 other. Iimer seta of the four reduced to a omtc tfimaite, as in the oor> 

 l e a poo di ai one of the two. while the one next to it nuiy be nearly 

 one-third shorter than the aormaL Labiom oocasia«ally with four 

 rocntalt. two of which are rvducad in aiac; cipedally m one aide. 

 Lateral setae six. Lateral lobe with three didiact teeth above the end 

 book, preceded by three tntnute teeth between which project two 

 Bptnttles. Femora vrith dark safaapkal rings. Tibiae with dark bnsal 

 rin«. c;itU lanceohte : widest jast beyond the nnddle. with blunt tips : 

 |iniximal half of their ventral oMrgiB* itraighl and scroagly spiaaloae: 

 tlie dorsal margin slightly oonvcs. somewhat spianlosc: distal margin 

 bearing a few kwg hairs. GiUs hyaline with foor or five wide. dark, 

 laccy bands formed by pigment eovcrmg the tradMH 



D t mea ri o m . Body iJ>ij naa.: giOs 5.5 aaa. 



"I Tup Sriinn^tD DllKJtPlilC FkMALI or I8CHVIW* viEi- 



TiCAUS Say. 



The dit I of the female of variom tpecks of isch- 



Nil •• acoqucd, two fonnt having been 



<l« tid bUck fcnnles of Itchmtrc vtrti- 



caks Say in the keys of Calvert ('93). WiUaniton ('00). and 

 others. According to Williamaon. both become prtiBKMe. the 

 hhck female lest so than the oranfe. He also notes that the 

 prutnose oranfe females are more ntmierous in the spring than 

 the bright orange or black ones, while the black females arc 

 most numerotu in the antumn. Sinoe it teemed probable that 

 these three forms might Ik difTerent ttages in coloration dtie to 

 age, tome ex perimentt were tmdertaken to determine their 

 relationship if possible. The results have proved that there b 

 btit one fetnale for Ischnmra i^eriicaiis Say. 



Apporaius. — The banks of Catcadilla Pdnd arc ttraiglit 

 and gratt grown. Into one of thcte bankt a cut wat made to 

 that abottt ten inches of water might ran into the bay Ihtis 

 formed. A simple cage was btrilt to cover this bay together 

 with a bit of the bank. The framework was nude by crossing 

 two pieces of heavy wire to form the diagonab of this rectangu- 

 lar space. The wires were bent at the oomert to that when 

 placed firmly in the ground they made a framework ten inches 

 high. Over this tupport a covering of white mosqtiito netting 



