THE HUNTING SPIDERS 203 



opening, and in this form is comparable to the wafer doors of the 

 true trap-door spiders. 



Mary Treat was the first to describe the burrow of the tiger 

 wolf; she observed over an extended period the life and general 

 activities of a colony of twenty-eight of these spiders. In spite of 

 their well-camouflaged nests, half of which were sealed during 

 most of August, all but five tiger wolves fell victims to the digger 

 wasps during that month. Those that escaped had completely ce- 

 mented down the lids of their nests until the wasp season was over. 

 Such a tremendous toll seems to suggest that aspersa is no safer 

 living underground than her several close relatives, which rarely 

 dig into the soil, and then make only a shallow cavity. 



In the southeastern part of the United States live many large 

 Lycosae to which the common name "sand wolves" may be applied 

 with considerable accuracy. A representative species, the most 

 widely distributed of the whole series, is Lycosa lenta, a pale wolf 

 covered evenly with grayish hairs and only lightly marked above 

 by a dusky pattern. Intensive daytime collecting in Florida, where 

 these sand wolves are most numerous, rarely produces examples of 

 the several different varieties; at night, however, under the rays of 

 the headlamp barren areas and seemingly unproductive habitats be- 

 come bejeweled with their eyes, and it is possible to capture quarts 

 of specimens within a short time. 



These wolves are extremely abundant on white sands, where 

 they lie quietly with their legs outspread. They have fine eyesight, 

 but rely almost entirely on touch to capture insects. When the sand 

 is tapped with a pair of forceps, the spider rushes over to grasp 

 and w T restle with the instrument almost as it would with normal 

 prey. Most intriguing of all the sand wolf's reactions occurs when 

 it is disturbed: It turns a somersault, dives into the sand, and disap- 

 pears, leaving on the smooth surface no sign of where it has gone. 

 Careful investigation shows that there is a well-hidden burrow 

 closed by a perfectly concealed trap door. This door is coated 

 above by a fine layer of sand; it is very thin, even thinner than the 

 most tenuous wafer door of the trap-door spiders but essentially 

 similar to it. The sand wolf opens the lid quicky and crawls head- 

 first into the cavity, closing the door after her with her legs. 



The burrowing life has left such small imprint on the bodies of 

 its practitioners that they appear to differ in no important respects 

 from the vagrant wolf spiders. They produce subterraRean dwel- 

 lings comparable in excellence to those of many trap-door spiders, 



