54 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
1. In Full Orb snares the spiral concen- 
tries cross all the radii, appearing to form 
complete circles. (See Fig. 47.) They are 
divided into Simple and Compound snares. 
a. A Simple orbweb is simply an orb of 
radiating straight lines crossed by spiral or 
looped lines. The snare of the Furrow spi- 
der (Epeira strix) is a typical example. 
b. A Compound orbweb adds to the sim- 
ple orb a system of netted or retitelarian lines 
crossed and joined at different angles, and 
placed above and on either side of the upper 
Fia. 49, Subdivisions of an orbweb. part of the orb, or placed below the orb. The 
snare of the Labyrinth Spider (Epeira labyrinthea) is an example. Sim- 
ple orbicular snares may be approximately arranged into three groups 
according as they have the Hub Meshed, Sheeted, or Open. 
I am not aware that any arrangement, description, or nomenclature of 
the various parts of the orbweb has ever been attempted apart from the 
following, which will therefore be found convenient and perhaps 
sufficiently comprehensive.1 The orb may be naturally: divided 
into the Central Space, CS, the Spiral Space, SS, and the Foun- 
dation Space, FS. (See Fig. 49.) 
The Central Space is included between the centre of the orb and the 
origin of the Spiral Space. It has three 
distinct parts, the Hub, the Notched zone, 
and the Free zone. The Hub is a small 
circular part immediately surrounding the 
centre, which is either wholly open, or 
covered in whole or in part by spinning- 
work. 
1. The Meshed Hub is wholly or partly 
covered by a series of irregularly shaped 
meshes, through which one can often trace 
the continuation of the radii as zigzag lines. 
In fact, it may be considered as a small 
rudimentary and irregular orbweb (Fig. 
50). Usually it nearly corresponds in size 
to the length (including the legs) of the 
spider that has woven it. 
The spider when waiting for her prey 
upon her snare is frequently and at night = 
generally stretched upon or near this hub, — .50. Meshed hub and central space. 
Parts of 
the Orb. 
1 First published in “Our Continent,’ Philadelphia, No. 33, page 362, 1882, and “ Pro- 
ceedings of the Academy of Natural Sciences,” Philadelphia, 1882, page 207. 
