OF WASHINGTON. ' 241 
Coleoptera those species which, in my opinion, are to be considered as 
accidental or occasional visitors or intruders in ants' nests. Many of these 
species recorded by former observers were already considered as doubtfully 
myrmecophilous by Dr. Hamilton. This list of accidental visitors could 
be still greatly extended from unpublished material, but I mention here 
only the following : 
Panagceus crucigerus, found hibernating in ants' nests (Hamilton}, 
with Lasius claviger (Pergande); Casnonia pennsylvanica, with Prenole- 
pis nitens (Pergande) ; Bembidium 4-maculatum; Tachys incurvus, found 
abundantly with Formica exsectoides (Blanchard) ; Colon (no species has 
been found among ants by American observers); Scydmcenus c a$ ill o stilus; 
S. brevicornis; Eumicms grossus, found with ants by Mr. Ulke;* E. Mots- 
chulskii, with Lasius alienus f Schwarz); Decarthron formisceti; Quedius 
molochinus* with Lasius claviger (Pergande) ; Leptacinus longicollis; Dio- 
chus Schaumii; Edaphus nitidus, found with Formica exsectoides and Aphte- 
nogaster fulva (Schwarz) ; Stictocranitis puncticeps; Lathrobium dimidia- 
tum, found with Prenolepis parvula and Cremastogaster lineolata (Per- 
gande, Schwarz); Lithocharis sp., with Solenopsis debilis (Pergande); 
Tachyporus brunneus; T. scitulus; Conosoma pubescens; Apocellus sphte- 
ricollis, found often with Ponera contracta (Pergande); Arpedium 
Sch wa rzi wi th Prenolepis parvula (Pergande); Eleusis pallidus; Pteni- 
dium evanescens; Hister Harr'isii, found with Camponotus pennsylvani- 
cusf (Hamilton), and possibly to be included among the myrmecophilous 
species ; Hister americanus, with Ponera contracta (Pergande) ; Meli- 
gethes brassicce; Cyphon padi; Pleurophortis ccesus, with Prenolepis fulva 
(Pergande); Atcenius cognatus, with Formica fusca and Aphcenogaster 
futoa (Pergande, Schwarz) ; Serica vespertina, with Formica Schaufussi 
and Lasitis interjecttis (Pergande) ; Diccdus punctatus, with Aphcenogaster 
fulva (Schwarz). 
REVISED LIST OF NORTH AMERICAN MYRMECOPHILOUS COLEOPTERA. 
The following list enumerates the true myrmecophilous species i. <?., 
those which live in ants' nests during all stages of development; further, 
those which are myrmecophilous only in the larva state, those which are 
myrmecophilous only in the imago slate, and those which are more fre- 
quently found among ants than elsewhere. But it includes also quite a num- 
ber of still doubtful species, for which it must be left to future observa- 
tion whether they are to be retained here or referred to the list of accidental 
visitors. For the bibliographical references of previous records the reader 
is referred to Dr. Hamilton's list. 
* The specimens found with ants at Washington, D. C., constitute, ac- 
cording to Mr. Ulke, a species distinct from the true E. grossus from Ala- 
bama and Florida. If this be correct, it has to be transferred, as Eumicrus 
n. sp., to the list of myrmecophilous species. 
