— 109 — 



Descriptions of some New Trap-Door Spiders; Their 

 Notes and Food habits. 



By Geo. ¥. Atkinson. 



A few months after sending the manuscript of the article. "A new 

 trap-door' spider"', to the publishers, I found a specimen which differed 

 so markedly in color from the one, the subject of that article, and agreed 

 so closely with the one described by Hentz as Mygale carolincnsis,'^ now 

 Pachylomertis carlinensis^ Hentz, that before having an opportunity to 

 study them carefully I concluded the only difference was in color. Just 

 after the article, ''A family of young trap-door spiders",* was in type I 

 discovered that the two forms were different species; that the one called 

 in the Amer, Nat. "Anew trapdoor spider", and the young spiders 

 whose work is described in the En to. Am. were both new species: the 

 former I have called Pach\lon:erus caribivrrus, and the latter Pachylome- 

 rtis- 4.spinosus. 



The nests oi P. larihvortis, and/*. 4-spitiosus. have already been de- 

 scribed in- the arcticles referred to. One thing however, in regard to P. 

 caribivorus is worth adding. The last trap-door made by this species as 

 described in the Am Nat, p. 590, was in shaip contrast, being made al- 

 most entirely of clay, with the surrounding mots. In a few days the 

 spider uiade an examination of its work and found it had made a mis- 

 take in not placing moss in the door. It remedied this as well as pos- 

 sible by cementing moss to the edge of the door and pressing the ends 

 down so that about half of the duor was covered with moss! 



Nest of Pachylomerns turris. March, 5, '86, on turning over an 

 old log, a sudden movement of an object downward attracted my atten- 

 tion, I looked and discovered a silken tube, with particles of earth and 

 leaf mould attached extending above ground. On one side the silk was 

 so extremely thin as to afford a "window'" to the spider's house! It was 

 through this that I had discovered the mo\'ement which attracted my at- 

 tention. Nearly the entire remaining portion of the tube was covered 

 with earth and leaf-mould, and here the silk was thinner than in other 

 portions, yet intact. It seems almost incredible, yet from the wonderful 

 intelligence manifested by these spiders, I was led to think this "window'" 

 had been purposely made: that the spider would sit by it and watch for 

 beetles crawling about under the log, and seeing one would rush out 



1 American Naturalist, Vol. XX, p. 583, July 1886. 



- The Spider.s of the United States, by Nicholas Marcellus Hentz, M. D., Boston 

 Journal, IV, p. 56. pi. VII, fig. 3. 



3 Heitriige zur Kenn'.niss der Territelariac, Aiisscrev, p. 147. 

 ■• Entomologica Americana, August 1886. 



