A MONOGRAPH OF THE GENUS ACRORICNUS. 171 
[Of the remaining five species included in this genus, the 
three described from Brazil by Taschenberg (Zeits. Ges. Nat. 
1876, pp. 71-74) have not been mentioned since first brought 
forward ; nor has A. edwardsi, Cress. (Proc. Acad. Philadelphia, 
1878, p. 365); though the last, A. cloutiert, Provancher (Natural. 
Canad. 1874, p. 150), has twice been figured (lib. cit. 1879, 
p. 110, fig. 2b et Faun. Ent. Canad. Hym. 1883, p. 348, 
fig. 35ab)./ 
1. ACRORICNUS MACROBATUS, Grav. 
Cryptus macrobatus, Gr. Ichn. Europ. 1829, ii. p. 440; Acroricnus 
schaumu, Ratz. 1852, p. 92. 
The only species with entirely black abdomen and meta- 
thorax. Folard sent a pair to the Rev. T. A. Marshall from 
Avignon in August and September, 1891-2; of two in Ruthe’s 
German collection, one was captured by Bermuth, possibly with 
Ratzeburg’s type; Dr. L. W. Sambon found a female in Ostia 
during 1901; and Bucheker had the species from Lagern on 
August 8th in “ Alp. That.’ in the Engadine above St. Moritz, 
from Zurich on July 1st, and elsewhere in Switzerland. This is 
the only British species of the genus, and has hitherto been 
known only from the extreme south— Hampshire, Isle of Wight, 
and Devonshire—though there appears to be no reason for 
supposing it confined to those counties, since Dr. A. Roman tells 
me that in Sweden it extends ‘‘at least as far north as western 
Dalecarlia’”’ (latitude 61°—that of the Shetland Islands)—and 
that it is there not rare in dry localities. Its known British 
range is, however, extending, for I have recently seen specimens 
from Romsey in Hants (Buckell), Milford Haven in Wales on 
June 4th, 1910, and Stradbally, co. Waterford, in Ireland, at the 
end of June, 1907 (Andrews). It is known to parasitise several 
species of the wasp genus Humenes and the bee genus Osmia. 
2. AGRORICNUS SEDUCTOR, Scop. 
Ichneumon seductor, Scop. Delic. Faun. 1786, p. 57 ; Xenodocon 
ruficornis, Forst. 1855. 
A large and handsome black and flavous species ; occurring 
on both north and south shores of the Mediterranean from 
- Provence to Algeria, but probably commonest in Italy. The 
Rey. T. A. Marshall told me in 1898 that he was then noticing 
the species abundantly about the nests of a wasp in stone walls 
at Ajaccio in Corsica, but his collection contains but a single 
example sent by Folard, who took it at Avignon on October Ist, 
1892 ; I possess the species from Oldenberg’s collection, taken 
in the middle of July, 1899; and the British Museum has a 
short series, taken in Italy by Birch, as well as in Albania 
between 1848 and 1850 by Sir Sydney Saunders, who says of 
one particular male there ‘‘ Parasite on Pelopeus spirifex,”’ 
