16 



Class. ARACHNIDES. 



Order. Pulmonaria. 



Family. Araneides. 



Section. Tetrapneumones. 



Genus. Mygale. Walckenaer. 



Characters. Eyes eight, placed near together on the anterior 

 edge of the cephalothorax, in two roivs, variously curved; fang 

 of the cheliceres articulated downward; palpi inserted on the 

 extremity of the maxillai ; feet 4. 1. 2. 3 or 4. 1. 3. 2. 



Observation. The distinction between Mygale and Oletera 

 is artificial, as a slight elongation of the maxillas of Mygale 

 would place the palpi at the side ; witness Mygale ? unicolor. 



1. Mygale truncata. 



PI. I, fig. 1. a. Eyes. b. Trophi. c. Side view of the Spider, d. Hole 

 in which it resides. 



Description. Piceous ; cephalothorax with a curved impres- 

 sion behind the middle, cheliceres (mandibular) terminated by 

 several points above the fang, hairy ; abdomen cylindrical, 

 suddenly truncated at the end, and callous at that place, with 

 concentric grooves and six circular impressions ; thighs more or 

 less rufous at base ; a white membrane between the joints. 

 Feet 4. 1. 37~2. 



Observations. This spider dwells, like other species of this 

 subgenus, in cylindrical cavities in the earth. Though many 

 specimens were found, I never saw the lid described by authors 

 as closing the aperture of its dwelling. The very singular 

 formation of its abdomen, which is as hard as leather behind, 

 and which forms a perfect circle, induces me to believe that it 

 closes with that part, its dwelling, instead of with a lid, when 

 in danger. • 



Habitat. A la Kama. 



