A HISTORY OF NOTTINGHAMSHIRE 



minute millipede, occurs under stones and bark of dead trees in several localities. The ' pill-milli- 

 pede,' Glomeris margmata (Vill.), is a short broad millipede of the size and shape of the common ' pill- 

 woodlouse,' which it also resembles in its ability to roll up into a spherical ball when disturbed. 

 It is however easily distinguished from the woodlouse by the large size of the posterior segment of 

 the body, and by the narrow white border to each segment. 



Of the family Polydesmidae one species, Polydesmus complanatus (Linn.), is very common with 

 us, occurring chiefly under rotten logs lying on the ground. Other species will probably be 

 found among the material collected by the writer when properly examined. 



Atractosoma folydesmoides (Leach), belonging to the family Chordeumidae, has been found in 

 Nottingham. 



Individuals of one or more species of the lulidae occur abundantly in Nottinghamshire, and 

 are locally known as ' wireworms.' 



ARACHNIDA 



Spiders, Harvestmen, and False-scorpions 



Spiders may be readily distinguished from insects by the following characters among others : 

 In insects the body is clearly divided into three separate regions head, thorax, and abdomen, the 

 last-named being distinctly segmented, while in spiders the head and thorax are completely fused 

 together, forming the cephalothorax, which is connected with the abdomen by a short stalk or 

 pedicle ; only two distinct parts are therefore visible ; the abdomen is not segmented. The eyes of 

 spiders are simple, while insects possess compound eyes, although many have simple eyes in addition. 

 Insects have three pairs of legs, spiders possess four pairs. In front of the walking legs all spiders 

 possess two pairs of jointed appendages ; the anterior of these are called the chelicerae or falces, and 

 are formidable claw-like pointed fangs, each containing a poison-gland ; these are used for seizing 

 and killing the prey. The hinder pair are the pedipalps or palpi ; they lie on either side of the 

 mouth, and the basal part of each (the maxilla) is used as a masticatory organ, while the remaining 

 portion forms the palpus or feeler ; the terminal joint of this is in the male spider modified into an 

 accessory organ of reproduction. 



The terminal joint, or tarsus, of each of the eight legs ends in either two or three curved 

 claws, and in some spiders there is on the last joint but one (metatarsus) of the fourth pair of legs a 

 peculiar comb-like organ termed the ' calamistrum,' consisting of a longitudinal row of curved 

 bristles. 



The silken lines which all spiders produce are emitted from a group of six nipple-like ' spinners ' 

 situated on the underside of the hind end of the abdomen. In those spiders which possess a 

 calamistrum there is also, immediately in front of the spinners, a paired organ, the so-called 

 ' cribellum,' perforated by numerous fine pores through which silk is emitted and combed out by the 

 calamistrum so as to become flocculent, and to assist in the entanglement of their prey. 



The respiratory organs of spiders are tubular tracheae and book-leaf tracheae (' book lungs ') 

 opening to the exterior by slit-like apertures or stigmata situated in the anterior part of the under- 

 side of the abdomen. Some have book-leaf tracheae only, others possess both book-leaf and tubular 

 tracheae. 



Unlike most insects, spiders undergo no metamorphosis, but they moult or cast their skin 

 several times before reaching the adult state. All spiders are carnivorous, preying upon other 

 animals, chiefly insects, which they capture either by leaping suddenly upon them, or more com- 

 monly by spinning webs or snares in which the insect prey becomes entangled. 



In the Phalangidea or harvestmen the body is undivided, the abdomen being joined to the 

 cephalothorax along its whole breadth, instead of being connected with it by a narrow pedicle as 

 in spiders. The abdomen is segmented, the eight legs are very long and slender, and the simple 

 eyes are only two in number. 



The Chernetidea or false-scorpions are minute arachnids occurring amongst moss and dead 

 leaves, or under stones, etc., and easily recognized by their peculiar palpi, which are very large 

 and terminate in pincers or forceps. They thus resemble miniature scorpions, except that they 

 have no tail. 



Nothing whatever appears to have been known concerning the arachnids of Nottinghamshire before 

 1903, when the present writer began to pay attention to them for the purposes of this History. In 

 the course of two seasons' collecting 169 species of spiders, fourteen species of harvestmen, and five 

 of Chernetidea have been taken in the county, and while more extended research will doubtless result 

 in the discovery of many more species, the list given below will compare favourably with those of 

 most other counties whose arachnid fauna has been worked out. In the preparation of this list the 



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