8 ILLIXOIS BIOLOGICAL MONOGRAPHS [402 



Nickerlea ; Australia _ 2 



Rhysopleura ; Australia 1 



Euprosopus; Brazil 2 



Langea; Peru 1 



Iresia; coutinental tropical America 8 



Tlierates ; ilalay Archipelago 33 



Odontoehila; South America, Malay Pen. and 



Islands 75 



Prepusa ; South America) 3 



Oxygonia ; South America 15 



Opistheneentrus : Brazil 1 



Cieindela ; world-wide distribution 686 



Eurymorpha; Africa _ _ 1 



Apteroessa; India 1 



1299 

 The group contains some 35 genera and upwards of 1300 species 

 and subspecies. In the figures above the subspecies of Cieindela number- 

 ed in Roman in Horn's Genera Insectontiu list, -which number 55, are 

 included, but subspecies numbering more than 8 in llegacephala alone, 

 and several in other genera, are not included. 



There are very few of these 1300 races which the writer has not 

 seen in some one of the particularlj^ numerotis and complete collections 

 studied. Those studied quite completely are : British Museum of Natural 

 History ; Hope Collection, Oxford University ; Cambridge University ; 

 Private Collection of Mr. Basil G. Nevinson, London ; Private Collection 

 of Dr. Walther Horn, Berlin; Zoologisches Museum, Berlin; Private 

 Collection of Doctor Gestro, Genoa ; Jardin des Plantes, Paris ; Museum 

 of Comparative Zoology, Cambridge, ^Massachusetts ; United States 

 National Museum ; Philadelphia Academy of Science : American Museiuu 

 of Natural History, New York ; and the University of Chicago collection 

 including an old collection once the property of John Akhurst, Brook- 

 lyn, several purchases from Hermann Rolle of Berlin, and the material 

 secured by exchange for other species in the Akhurst collection, and 

 material purchased and collected for the writer by the University, and 

 specimens collected on the excursions supported by the University. In 

 addition to this the writer secured a collection of exotic material from 

 Mr. John D. Sherman in exchange for Dytiscidae and numerous speci- 

 mens by exchange and gift from numerous American and foreign collect- 

 ors. Of the few species not seen several are represented in figures which 

 show the color patterns. 



Many of the drawings presented are from the collections in ques- 

 tion ard arp appropriately designated in the groups of figures in th" 



