CRYPTOHYPNUS RIPARIUS, A POSSIBLE PEST 181 
(CU VAP ONS VAZIM OLS, IKIUPGUSIUOS, IN (CU Kole) DAMES; 
IMS) MOSSES, ANGI CUIC ANON AU, Tela She 
By WILLIAM EVANS, F.R.S.E. 
WHAT are wireworms? and, Which is the common species 
of Agriotes in Scotland? These are questions that have 
been put to me from time to time during the past few 
years by allotment-holders and others interested in the 
Cultivation: of theslands ihe answer ito “the. first it) is 
hardly necessary to say, has been—True wireworms are 
the larve or grubs of Click-beetles, belonging typically 
to the genus Agriotes, as to which see the Board of Agri- 
culture’s leaflet No. 10; and to the second—Agvzotes 
obscurus undoubtedly. In the Lothians, and I believe in 
other parts of Scotland as well, this is an abundant and 
generally distributed insect, while 4. “ueatus and A. sputator, 
the other members of the genus included in the leaflet, 
are of rare occurrence. But with us the most common 
Click-beetle, both on land under cultivation and on natural 
pasture, is not an Agvrzotes but a Cryptohypnus, namely, 
C. riparius, F., a species apparently rare in the south of 
England, and not mentioned, so far as I can make out, 
in the literature of insect pests in this country. Its yearly 
presence, at times in large numbers, on farm lands suggests 
that it may be responsible for not a little of the damage 
caused by wireworms in Scotland. The only genus other 
than Agrzotes which the Board’s leaflet recognises as a pest 
is Athous, but our common species, A. hemorrhotdalcs, 
prefers, in my experience, rough uncultivated places to fields. 
In Fowlers “British Coleoptera,’ the habitat of 
Cryptohypnus riparius is given as “the banks of streams, 
etc., under stones and pieces of wood, also in flood refuse.” 
This is misleading, for it may be found almost anywhere in 
open country on natural grassy places and cultivated ground 
alike. I have met with it from sea-level to the tops of the 
Pentland Hills. The following observations show how exten- 
sively land in cultivation may be infested by it. 
I19Q AND 120 Z 
