Spiders and Their Near Relatives 



in the United States by two genera, Acanthophrynus and Tarantula. 

 These are separated as follows: 



A. Front border of the cephalothorax armed with long teeth; 

 next to the last segment of the pedipalp with only one 

 long spine on the upper inner margin. P. 20. 



Acanthophrynus 

 AA. Front border of the cephalothorax unarmed or only dentic- 

 ulate; next to the last segment of the pedipalp with at 

 least two long spines on the upper inner margin. P. 20. 



Tarantula 



The genus Acanthophrynus includes only a single known 

 species, Acanthophrynus coronatus (A-can-tho-phry'nus cor-o- 

 na'tus); this is found in California and Mexico. This species is 

 larger than those of the following genus, attaining a length of 

 nearly two inches. 



The genus Tarantula (Ta-ran'tu-la) is represented in the 

 United States by three species. We have here an unfortunate 

 instance in which the technical and popular uses of a name are 

 very different. For although, according to the law of priority 

 the generic name Tarantula must be applied to these animals, 

 the popular name tarantula is irrevocably applied, in this country 

 at least, to the large four-lunged spiders of the South and the 

 Southwest. 



Four species of Tarantula are known; these are separated by 

 Kraepelin as follows: 



A. With two short spines between the longest spines of the tibia 

 of the pedipalps. T. fusimana 



AA. With only one short spine between the longest spines of 

 the tibia of the pedipalps. 

 B. The intermediate spine between the two principal spines 

 of the pedipalps considerably longer than the spine 

 immediately preceding the first of the two principal 

 spines. T. whitei 



BB. The intermediate spine shorter than the one preceding 

 the first of the principal spines. 

 C. The principal spine on the upper edge of the next to 

 the last segment of the pedipalps preceded by a dis- 

 tinct spine (Fig. 19). T. palmata 



20 



