PSYCHE. 



ON COLEOPTERA FOUND WITH ANTS. (FOURTH PAPER.) 



BY H. F. WICKHA.M, IOWA CITY, IOWA. 



The following notes are intended to 

 be supplementary to those which I have 

 contributed to earlier numbers of Psyche. 

 While fragmentary, they will add some- 

 thing to the knowledge of our native 

 Myrmecophiles. 



A reexamination in May, 1S96. of the 

 nest of Formica obsciiripcs (at Iowa City) 

 from which the specimens of Platymedon 

 latkoUe had been taken in preceding 

 years, showed that for some cause the 

 ants had deserted it and moved to an- 

 other locality a few feet distant. On 

 digging into this new nest it was seen 

 that the Platymedon had followed its 

 host since more than twenty specimens 

 were obtained. Anthicus melancholicus 

 had also accompanied the ants to their 

 new home, but I found them more abun- 

 dant in the old deserted mound than in 

 the fresh one. Early in 1897 I again 

 went out to visit this colony and found 

 it so weak that I judged it better not to 

 disturb it, particularly as no other colony 

 of this species has ever been noticed in 

 this part of Iowa. Lately Mr. A. W. 

 Hanham sent me specimens of the same 

 Platymedon, captured with F. obsciiripes 

 near Brandon, Manitoba; he took them 



by placing flat stones on the nest, when 

 on his return a week later (April 23rd) 

 the beetles were found beneath them. 

 Some, he writes, got away before he 

 could catch them — and indeed the little 

 creature is very quick in its motions and 

 makes the most of the opportunities for 

 concealment afforded by the debris com- 

 posing the mound. In the same nest 

 Mr. Hanham took larg-e numbers of the 

 case-bearing larvae of Coscinoptera doni- 

 hiicana, April i6th. The cases, he says, 

 were nearly as numerous as the ants and 

 were generally attached to the twigs of 

 which the mound seemed to be chiefly 

 composed. The first beetles were dis- 

 closed May 17th and are of the densely 

 pubescent type noticed by Dr. Horn as 

 belonging more particularly to western 

 specimens. 



A species of Stilicus sent from Win- 

 nipeg by Mr. Hanham seems undoubt- 

 edly new and is described below. It is 

 said to be found under stones in com- 

 pany with ants through the earlier part 

 of the season, having been taken at 

 various dates between April 22nd and 

 May 25th. Mr. Hanham writes, in reply 

 to a query, whether the insect should, 



