The type species, H. paradoxus, is very rare in England, and though small and inconspicuous, it is certainly one of the most curious members of our Spider fauna.
Fam. 25. Archeidae.—This small family includes certain remarkable fossil spiders from Baltic amber, and two rare recent forms, Archea (Eriauchenus) workmani from Madagascar, and Mecysmauchenius segmentatus from America. The chelicerae, which are extraordinarily long, are articulated far away from the mouth-parts. The caput is clearly marked off from the thorax, and is much raised. In several other respects these spiders are very distinct from all other members of the order.
Fam. 26. Mimetidae.—The Mimetidae form a small group in general appearance recalling the Theridiidae, with which family they were for a long time incorporated. The chief genera are Ero, Mimetus, and Gelanor. Ero furcata (= thoracica) is a pretty little spider, not rare among grass in England. The upper side of its very convex abdomen is marked with red, yellow, and black, and bears two little protuberances or humps near the middle. It is only about an eighth of an inch long. Its interesting egg-cocoon has already been alluded to (see p. [358]). E. tuberculata has been found on rare occasions in this country. There are about ten other species of Ero, all small spiders, and living in temperate regions. The genus Mimetus (in which is merged Blackwall’s Ctenophora) includes a number of larger, more strongly-built spiders, living for the most part in tropical countries.
The genus Gelanor (Galena) is the American representative of the group, its three species being rather large spiders, inhabiting Central and South America. The males of this genus have remarkably long and slender pedipalpi, much longer than the whole body.
Fam. 27. Thomisidae.—The Thomisidae are the Latigrade spiders of Latreille, and the “Crab-spiders” of popular nomenclature. Their legs are extended more or less laterally instead of in the normal fore and aft directions, and their progression is frequently strikingly crab-like. They form a very large group of more than 140 genera, including spiders of every size, and they are to be found in every quarter of the world. Forty-three species are British. Many strange forms are included in this group, and several of the sub-families into which it has been divided contain only one or two genera. The bulk of its members fall into the sub-families Thomisinae, Philodrominae, and Sparassinae.
(i.) The Thomisinae (Misumeninae of Simon’s Hist. Nat.) include what may be called the more normal members of the family, distributed among more than sixty genera. Six of these genera are represented in the British Isles. Our commonest Crab-spider is probably Xysticus cristatus, abundant everywhere in grass and herbage. Young specimens may often be seen upon iron railings in the autumn. Twelve other species of that genus are on the British list. They are of small or moderate size, rarely exceeding a quarter of an inch in length. A closely allied genus is Oxyptila, of which we have seven species. The more striking members of this sub-family to be found in England are our single representatives of the genera Misumena, Diaea, and Thomisus. Misumena vatia is a handsome species, the female measuring sometimes more than a third of an inch, and having its large yellow or green abdomen marked, in many specimens, with a pair of bright red bands, which, however, are not always present. The males are much smaller and darker. It is common in some parts of England, especially in the south, where it is to be sought for in bushes and trees.
Fig. [213].—Thomisid spiders. A, Micrommata virescens, ♀; B, Xysticus pini, ♀; C, Philodromus margaritatus, ♂; D, Tibellus oblongus, ♀.
Diaea dorsata is one of our prettiest British species, with light green legs and cephalothorax, and a yellow abdomen with a red-brown central marking. It is common in the New Forest and other southern localities. The female attains a quarter of an inch in length.
Thomisus onustus, a rare spider among heather, is recognisable by the shape of its abdomen, which is broadest behind and abruptly truncated. When adult the abdomen is a pale yellow, but the young are suffused with a pink hue closely corresponding with that of the heather blossom in which they are frequently found sitting.