ON THE WASP-GENUS PARALASTOR. 563 
34. On the Species of Alastor (Paralastor) Sauss. and some 
other Hymenoptera of the Fanily Humenidee. By R. 
C. L. Perzins, M.A., D.i8e., F.Z.8. 
[Received April 9, 1914; Read May 19, 1914.] 
(Plate 1.*) 
INDEX. 
Ethology : Pages 
Paralastor, mimetic colour-groups of ............... 6... 563-565 
Geographical : 
Paratastor, am Australian Genus) 22. 5.).21..6 02. -20---e---e 563 
Systematic :' 
Paralastor, division of Alastor Sauss., raised to generie¢ 
PUN ra Seas raeea sore Gedennd ecieromae hacen Se 563 
A NE WeSPEGCIES Oli seh ecu eoess seen Seek eee) (B79=621 
Pseudozethus australensis, gen. et sp. N..........-....... 622-623 
JETT OPOCUIO COUSUREHKAD OR S\05 Wo ga3d06 bab 5d00ce 264 05a 464 oo dcr 623 
Abispa meade-waldoensis, Sp. 0. .....-...-seveeeee eee ee ees 623 
The name Paralastor was given by Saussure to one of the several 
divisious of the genus Alastor which were characterized by him. 
It includes all the species of the Australian region, except one, 
Paralastoroides clotho Lep., and this differs but little from the 
other Australian species. 
Paralastor is a valid genus, and has no close affinity with the 
non-Australasian forms included in Alastor. Its most remark- 
able character lies in the structure of the antennz of the male, the 
peculiarities of which were quite overlooked by Saussure, as they 
were also in other genera of Eumenide, such as Abispa and 
Pachodynerus. The antenne of Paralastor g consist always of 
eight well-developed joints, followed by four, three, or two small, 
or often very minute, ones. This deficiency in the normal 
number of joints of the male is always accompanied in both sexes 
by a thoracic structure, so different from that of the Alastor of 
other countries that the genus is extremely well defined. The 
thoracic characters have been so clearly stated by Saussure that 
it is not necessary to repeat them here. 
The 8. African species Alustor brawnsi Meade- Waldo, and Alastor 
variolosus Bingham from Ceylon are members of one group, 
quite distinct from Paralastor, having ordinary male antenne 
with the normal number of joints (13), as in Odynerws and like 
European Alastor. On the other hand, the E. African Khynch- 
alastor fuscipennis M.-W. is more related to the S. American 
species, such as A. melanosoma Sauss., but the clypeus is pointed 
at the apex and the 2nd ventral segment of the abdomen has a 
costate sulcature followed by a deep large impression, and is not 
merely flattened between lateral carinations. 
The coloration of the species of Paralastor is interesting, in 
that, like the Odynerus of the Hawaiian Islands and elsewhere, 
* For explanation of the Plate see p. 624. 
