Fig. 37.—Sceliphron nigripes ♀ (Sub-Fam. Sphegides). Amazons. × 3⁄2.
It should be noted that in the solitary as in the social Insects the males take no part whatever in these industrial occupations, and apparently are even unaware of them. It is remarkable that, notwithstanding this, the sexual differences are in the majority less than is usual in Insects. It is true that the various forms of Scoliidae exhibit sexual distinctions which, in the case of Thynnides and Mutillides are carried to an extreme degree, but these are precisely the forms in which skill and ingenuity are comparatively absent, the habits being rather of the parasitic than of the industrial kind, while the structure is what is usually called degraded (i.e. wingless). The great difference between the habits of the sexes, coupled with the fact that there is little or no difference in their appearance, has given rise to a curious Chinese tradition with regard to these Insects, dating back to Confucius at least.[[45]] The habit of stinging and storing caterpillars in a cell, from which a fly similar to itself afterwards proceeds having been noticed, it was supposed to be the male that performed these operations; and that when burying the caterpillars he addressed to them a spell, the burden of which is "mimic me." In obedience the caterpillars produce the wasp, which is called to this day "Jiga," that is in English "mimic me." The idea was probably to the effect that the male, not being able to produce eggs, used charmed caterpillars to continue the species.
Summary of the Prey of Fossores.
| Group of Fossores. | Food or Occurrence. | |
| Fam. Scoliidae. | ||
| Sub-Fam. | Mutillides | As parasites on Hymenoptera Aculeata. |
| " | Thynnides | (?) Parasites on Lepidopterous pupae. |
| " | Scoliides | Larvae of Coleoptera [(?) spiders in the case of Elis 4-notata]. |
| " | Rhopalosomides | Unknown. |
| " | Sapygides | The provisions stored by bees. Caterpillars (teste Smith). |
| Fam. Pompilidae | Spiders. Rarely Orthoptera (Gryllidae and Blattidae, teste Bingham) or Coleoptera. | |
| Fam. Sphegidae. | ||
| Sub-Fam. | Sphegides | Orthoptera (especially Locustidae), larvae of Lepidoptera, Spiders [(?) same species (Sceliphron madraspatanum and Sphex coeruleus), both spiders and caterpillars]. |
| " | Ampulicides | Orthoptera (Blattidae only). |
| " | Larrides | Orthoptera of various divisions. Aculeate Hymenoptera, in the case of Palarus. [Spiders stolen from nests of Pelopaeus by Larrada.] |
| " | Trypoxylonides | Spiders, caterpillars, Aphidae. |
| " | Astatides | Astata boops uses Pentatomid bugs, cockroaches, and even Aculeate Hymenoptera (Oxybelus, teste Smith). |
| " | Bembecides | Diptera and Cicada. |
| " | Nyssonides | Diptera, Homoptera (Gorytes mystaceus takes Aphrophora out of its "cuckoo-spit"). |
| " | Philanthides | Aculeate Hymenoptera (Philanthus). Hard beetles, viz. Curculionidae, Buprestidae, Chrysomelidae (Cerceris). |
| " | Mimesides | Small Homoptera, even Aphidae. Diptera (Tipulidae) in Hawaii. |
| " | Crabronides | Diptera, Aphidae [? the same species of wasps both of these]. Other small Homoptera. Ants (in the case of Fertonius). Parasitic Hymenoptera (in the case of Lindenius). |
Great diversity of opinion exists as to the classification of the Fossores. This arises chiefly from the incomplete state of the collections studied, and from the fact that the larger part of the works published are limited to local faunae. Opinions as to the families vary; some admitting only three or four, others upwards of twenty. After consideration of the various views, the writer thinks it best to admit at present only three families, which speaking broadly, correspond with habits, viz. (1) Scoliidae, subterranean stingers; (2) Pompilidae, runners; (3) Sphegidae, stingers above ground.
1. Scoliidae. Pronotum and tegulae in contact. Abdomen with the plane of the ventral surface interrupted by a chink between the first and second segments. Numerous wingless forms.
2. Pompilidae. Pronotum and tegulae in contact. Abdomen with the plane of the ventral surface not interrupted by a chink. Legs very long. No wingless forms.
3. Sphegidae. Pronotum and tegulae not in contact. No wingless forms.
We shall treat as sub-families those divisions of Scoliidae and Sphegidae considered by many as families.