281 



The four species of Proctotnjpes produce only single para- 

 sites from the individual eggs in the spider's nest. The 

 four Chalcididae are secondry parasites attacking the para- 

 sitic Hymenopterous and Dipterous larvæ that are already 

 in the spider's nest. The Ichneumons do not restrict them- 

 selves to individual eggs but attack the whole eggmass, 

 living free in it and consuming the entire eggmass or the 

 greater portion of it. The larva of Polyspliincta varipes 

 sometimes even attacks and consumes the female host to- 

 gether with the eggs. Of the Dipterous larvæ 3 live free 

 in the eggmass, whilst the fourth Acrocern cjlobulus Panz. 

 is an internal parasite on a Pardosa. Acams consume the 

 eggs in the nests of several different Tberidions that live 

 on the ground. Filaria is an internal parasite on Zora ma- 

 culata and several Lrjcosa. 



Bæiis Hal. This is the first time that it has been able 

 to state where any of the european species of this genus 

 live. American naturalists have discovered that one of the 

 american species was parasitic on spiders' eggs. Ash mead 

 in his Monograph of the North American Proctotrypidae 

 Wash. 1893 p. 180 states that Bæus americamis How. has 

 been bred from spiders' eggs and also states later that the 

 host was a species of Epeira. It is quite out of the question 

 to think that the european species are parasitic on Epeira, 

 and I schould also believe, from the experience I have ob- 

 tained from breeding Bæus, that the american species only 

 attack quite small spiders. This is the first time that the 

 male of Bæus seminulum Hal. has been obtained. The males 

 are exceedingly rare, from about a twenty breedings I have 

 only obtained two males, which are the only two known 

 specimens. (In the summer of 1909 I was fortunate enough 

 to breed two more.) 



Bæus seminulum Hal. The following is a discription 

 of the male: Head large, broader than Thorax. Forehead 

 broad, convex. 3 ocelli arranged in a triangle: the hindmost 

 near eyes and base of head. Eyes large, oval. Antennae 

 pale honney-yellow, fixed near clypeus, 11 -jointed, 2°"^ joint 



