Ephtaltes.] BRITISH ICHNEUMONS. 33 



"But it is scarcely proved that the larva of Chelostoma was the object of 

 attack : when we take into consideration the size of the parasitic lar\a and 

 that of the bee, we are inclined to suspect that the Pimplas attack was 

 upon some other insect. Where colonies of this bee are met with in 

 posts and rails, there arc usually also two Coleopterous insects, Melandrya 

 carahoides and Clytus arhiis, depositing their eggs; ... it is possible that 

 Pimpla attacks the larva of one of these insects, and not that of Chelostoma. 

 The only ichneumon which 1 know from observation to be a parasite ot 

 Chi'losfohia is Fatiiits asscchi/or: this insect has more than once been bred 

 from its nests. . . . Mr. Kirby mentions, in connexion with his description 

 of this bee, Ichmiimon femoralor, which his friend ViX. Trimmer found in 

 the nest of Chclos/oma'' (Smith, Cat. Bees. Brit. i88). I consider it far 

 more probable that Clytus was the host than the only bee suggested 

 throughout the Pimplinae. 



In "this connection must be noted what Westwood (Introd. ii. 141 : 

 quoted by Wood in Insects at Home, 324) says respecting evidently 

 another species of this genus ox Pcrilhoiis. " ]\[ay 29, 1830, I observed 

 a Pimpla with the ovipositor about as long as the body in the act of ovi- 

 position in a drv paling, which had been much perforated, and out of 

 which I had just dug a black Pcmphndon. The part in which the oviposi- 

 tor was introduced appeared to be quite solid. There are several very 

 minute blackish spots which were probably other places of insertion of 

 the ovipositor. When first observed, the insect had introduced about 

 half the spicula into the post, the part remaining uninserted being at a 

 right angle with the body, the valvulae being curved, thvir tips being 

 brought to the place of insertion, thus evidently strengthening the spicula 

 in its operations; the abdomen was at this time alternately turned from 

 left to right, and 7'icc versa, \\hereby a bradawl kind of motion was gi\en 

 to the spicula, enabling it to penetrate the wood to a greater depth. It 

 then alternately partially withdrew, and replunged the spicula into the 

 hole thus made, as though in the act of passing an egg or eggs, standing 

 all this while on the tips of the tarsi." No victim, however, was found 

 at the other end of the ichneumon's boring, which by no means proves 

 that such did not exist. 



It will be at once seen from tlie above that the elongate terebra is used 

 to reach larvae buried at some depth in wood or mortar, though the para- 

 sites appear nearly indifterent as to the species or even Order to which 

 their \ictims belong, since I'JpJiialles continiitis, Ratz., has been bred from 

 both Xemalus laiieis and the swellings on poplar twigs caused by Saperda 

 pnpiihiea ; PJ. glabra/iis, Ratz., from Tortrix sliohilonim and probably also 

 Plrnnbius abielis; PL populiieus, Ratz., from .SVj/c/ hylaeiformis and perhaps 

 Saperda popuhiea, though the latter host is more doubtful than authors 

 usuallv acknowledge; I'J. diseoloi, Brisch., from Dasy/ts caeritleiis and PJ.wti- 

 teriis balteatus ; PJ. ex/ensor, Tasch., according to Schmiedeknecht's syn- 

 onvmv, from Biorhiza terminalis and Grapholitha pactolana. PI. pusillits, 

 Ratz., was once bred from Molorchus umbel/a fa rum in apple wood by Nord- 

 linger; and Taschenberg gives /:'. messor, Grav., as preying upon the wax 

 moth {Galleria fue/lonel/a, L.) so destructive in British bee hives. 



The members of this genus are easily divisible into groups, though 

 the species of each are closely allied and all are similar in colour; the 

 first two are large species with cylindrical abdomens and hardly any trace 

 of tubercles ; the two following are of medium size with the abdomen 

 distinctly tuberculate and subfusiform ; the remainder are all smaller, but 

 sufficiently distinguishable by the features indicated in the following 

 table. D 



