Superfamily Arglopoidea 



Genus THANATUS (Than'a-tus) 



In this and the following genus the fourth pair of legs are 

 longer than the first pair; and the posterior row of eyes are more 

 strongly recurved than in the preceding genera. In this genus 

 the cephalothorax is but little if at all longer than wide; and 

 the anterior lateral eyes are closer to the anterior median eyes 

 than to the posterior median eyes. 



The species of Tbanatus resemble each other in general ap- 

 pearance and in colouration; they are all of a yellowish or grayish 

 red, with the abdomen marked with a lance-shaped band. Fifty 

 species are known, of which the two following have been described 

 from the United States. 



Tbanatus lycosoides (T. ly-co-soi'des). — This species va- 

 ries considerably in markings. Figure 619 is from a photo- 

 graph of an unusually well- 

 marked individual. The ceph- 

 alothorax is reddish yellow 

 with a median, longitudinal, 

 brown band, which is wide in 

 front and tapers to a point be- 

 hind; the sides of the cephalo- 

 thorax are streaked with brown 

 and red. The abdomen is light 

 above, with a slender, brown, 

 lance-like spot in front, which 

 reaches beyond the middle, and 

 with an undulating band on each 

 side of the hind part. The an- 

 terior median eyes are much smaller than the anterior lateral eyes. 

 In many individuals there are no markings on the hind 

 part of the abdomen. In others there are two indistinct longi- 

 tudinal brown bands in the position occupied by the undulating 

 bands shown in the figure. 



The female measures from one fourth to one third inch in 

 length; the male is a little smaller and has longer legs. This is 

 a widely distributed species. 



Tbanatus coloradensis (T. col-o-ra-den'sis). — This is a Wes- 

 tern species which differs from the preceding in that the anterior 

 median eyes are as large as the anterior lateral eyes 



548 



Fig. 619. THANATUS LYCOSOIDES 



