— n6 — 



had alive. June 20, I placed a Plerostichus tucu&Iandus 1 , Say, in the 

 bottle containing the nest of the spider. During the night the spider 

 came out of the nest, caught the beetle, ate it and ejected the hard parts 

 from the nest. July ist, it disposed ofa Plerostichus Sayi, Brulle. June 

 29 it ate a beetle of the genus Chlanius. At another time it ate three 

 good sized beetles of the genus Chloenius in one night. 



The observation which I made on Nidivalvata marxii in captivity arc- 

 very interesting. I noticed that at night the spider would throw its doors 

 wide open 2 as shown in fig. 1 7, Plate V. One evening I placed several 

 in the jar containing the nest. When an ant approached so near the 

 door as to send a communication to the spider'of its presence, the spider 

 sprang to the entrance, caught a door with the anterior legs on either 

 side, and pulled them nearly together, so that there was just space e- 

 nough left for it to s^e the ant when it crossed the opening. When this 

 happened, the spider threw the doors wide open, caught the ant, and in 

 the twinkling of an eye had dropped back to the bottom of the tube with 

 its game. This I saw repeated several times during the months of Jan- 

 uary and February. At one time I placed a large cricket in the jar. The 

 spider made several attempts to capture it but was not strong enough. 

 It would probably eat crickets when fortunate enough to catch one. I 

 think also that it would eat small carabid beetles, for I found several in 

 the moss where I collected the spider. I have found the remains of ants 

 in the nests. 



I have made no observations on Myrmekiaphila foliata in captivity, 

 but from the location of their nests it is quite evident that the members 

 of this species are extremely fond of ants, and seek to build their nests 



1 I am indebted to Prof. J. A. Comstock for the identification of the species oi 

 1 leetles. 



2 The position of Nidivalvata in the subfamily Erhidontina; shows its near rela- 

 tion to the Atypince. I have often been struck with its likeness to the Atypince, es 

 pecially in the kind of a nest it makes, and though I have never seen an Atypus, 

 nor one of its nests, I have often concluded that from the form of its nest it must be 

 somewhat similar to Nidivalvata in architectural habit, and that the presence of a 

 door, or covering for the entrance to its nest instead of being wanting, has been over 

 looked ; that in the cases where the nest was open, accident had removed the door. What 

 O. P. Cambridge says in Annals of Nat. Hist. 4th series, 1875, Vol. XVI, p. 240-241. 

 seems to me to indicate that Atypus is very similar in habit to this genus. Not only in 

 the form of the nest, but in its food habit. He says that on one occasion a nest which 

 apparently had no orifice was buried in a box of earth; subsequently the tube was ob- 

 served with a wide open mouth, and again was closed the following morning. The 

 spider probably opens the doors at night to watch for food, and closes them in the 

 morning as does N. marxii. 



