ig2 THE SPIDERS OF EPPING FOREST. 



The Araneaeare oviparous creatures, without metamorphoses, feeding upon 

 insects or other small animals which they capture either with or without the 

 aid of a silken snare. 



SUB-ORDER MESOTHELAE (Pocock). 



Upper surface of abdomen with traces of segmentation in the form of 

 distinct transverse plates. This small sub-order, of which we have no British 

 representative, may be regarded as a transitional group, visibly approximating 

 the Pedipalps, and, therefore, as the probable ancestral stock from which the 

 various spider families have developed. 



SUB-ORDER OPISTHOTHELAE (Pocock). 



Abdomen apparently non-segmented. A small anal tubercle is often 

 present which may reasonably be regarded as a vestigial segment, but no 

 known representatives of this sub-order possess any structure which could be 

 mistaken for the dorsal plates of the Mesothelae. 



SECTION I. MYGALOMORPHAE. 



Spiders with four laminated tracheae and with the fangs articulated so as 

 to permit of motion iu a vertical plane. 



The more ancient spiders included in this section exhibit striking affinities 

 with the Mesothelae The Mygalomorphae are ot large size and, as a rule, 

 not brilliantly coloured. One rather aberrant family is represented in this 

 country, namely, Atypidae. 



SECTION II. ARANEOMORPHAE. 



Spiders with two laminated tracheae (with rare exception) and with one 

 or occasionally two openings leading to tube-tracheae (absent in a few cases). 

 The fangs are articulated so as to permit of motion in a horizontal or oblique 

 plane. 



Although apparently developed from a group identical with or closely 

 allied to the Mesothelae, the earlier forms of Arachnomorphae do not 

 approximate the ancestral type so closely in some respects as do the 

 M ygalomorphae . 



We may conveniently divide the Araneomorphae into three 

 series, Dysderiformae, Drassiformae and Argiopiformae. 



SERIES I. DYSDtRU'ORMAE. 

 Spiders of an early type with six nocturnal eyes and generally two tube- 

 tracheal openings situated close to the laminal tracheae. The tarsus of the 

 male palpus closely resembles that of the female, the joint being entire or 

 occasionally very slightly hollowed. The palpal bulb is of extremely simple 

 structure, usually more or less of a flask-like form and containing a spiral 

 sperm tube. Palpal apophyses are not present. The genital aperture of the 

 female is a simple transverse opening provided with neither epigynal plates 

 nor clavus. The tarsal claws are sometimes two and sometimes three in 

 number. 



