SPIDERS OF THE FAMILY ATTIDAE COLLECTED IN 

 THE VICINITY OF AMES, IOWA. 



I. L. RESSLBR. 



In tiiis work with the Attids collected in the vicinity of Ames 

 the writer used Banks' arrangement in the separation of genera 

 and species. A , few of the specimens were collected by Prof. 

 C. P. Clillette in 1888-90 and identified by Banks in 1891 ; some 

 were collected during the summer of 1916 by L. S. Wells while 

 others weiv collected during the fall of 1916 and spring of 1917 

 by the writer, who has identified all except those that were 

 coUecte.l hy Prof. Gillette. . ^ 



'rtie bright colors of a number of the specimens have been lost 

 due to their Ifong preser\'ation in alcohol. Recentl}- there has 

 been adopted a preserving medium which will preserve without 

 destroying the colors. This medium is composed as follows : 



Glycerine 40 parts 



P'ormalin (-t per cent) 40 parts 



Alcohol (95 per cent) 20 parts 



It has been found that by allowing spiders to Ivecome thor- 

 oughly saturated with the above solution they can l>e pinned and 

 kept in the same manner as insects. A number of brightly col- 

 ored Epeirid-ae and Thomisidae have been mounted in this 

 manner for over a year and a half and they have retained all 

 of their brilliant colors and characteristic markings. 



Spiders of the family Attidae are commonly known as .jump- 

 ing spidei-s because of their quick jumping movements. They 

 are of small or of medium size, have a short body and stout legs, 

 the tarsi of which are furnished with two claws. Spiders of this 

 group can always be recogiiized by the arrangement of the eyes, 

 which -dVQ in three rows. The anterior row is on tne vertical 

 side of tlie face, and the median eyes are at least twice as large 

 as the lateral eyes. The posterior median eyes are very small, 

 and ar.^ situated just back of the anterior lateral eyes. The 

 posterior lateral eyes are from two to five times as large as the 

 posterior median eyes and are situated back of the posterior 

 median eyes. They constitute the posterior iimits of the ocular 

 quadrang-le. The ocular quadrangle is the area defined by the 

 eyespac^^ and occupies the entire head region. 



Unlike most families the length of the legs is variable. Emer- 

 ton, wh<," lias done veiy extensive work with the new England 



