XV CLASSIFICATION 415 



which ten or twelve species are known, some of which are very 

 widely distributed, though confined to hot regions. These spiders, 

 which are all large, are easily recognised by their extremely flat 

 bodies and the peculiar arrangement of their eyes, all eight of 

 them being placed more or less in a single transverse line. 



Fam. 28. Zoropsidae.^ — The Zoropsidae are cribellate spiders 

 of large size, with well-developed scopulae on tarsi and metatarsi. 

 The cribellum is divided, and the calamistrum, which is very 

 short, is not well developed. Most are inhabitants of hot regions, 

 where they hve under stones or bark. Zoropsis has six species, 

 chiefly inhabitants of North Africa, though representatives occur 

 on the European side of the Mediterranean. Acanthoctenus has 

 two species in South and Central America. 



Fam. 29. Platoridae.^ — The Platoridae are Thomisid-like, 

 medium-sized spiders, generally with a uniform yellow or brown 

 coloration. The spinnerets are their most characteristic features. 

 The median pair present a large flat surface studded with two 

 parallel rows of large fusulae, while the anterior pair are situated 

 outside them, and are thus widely separated. There are only three 

 genera, and very few species of this family. Flator insolens 

 is a Chinese species. Doliomalus and Vectius belong to South 

 America. 



Fam. 30. Agelenidae. — Sedentary spiders with slight sexual 

 dimorphism ; with three tarsal claics and devoid of scopulae. 



The Agelenidae spin a more or less extensive web of fine 

 texture, usually accompanied by a tubular retreat. Our com- 

 monest cellar spiders belong to this group, which may be 

 divided into three sub - families, Cybaeinae, Ageleninae, and 

 Hahniinae. 



(i.) The Cybaeinae include some sixteen genera, of which 

 two deserve special mention on account of the peculiar habits of 

 the spiders belonging to them. 



Desis is a genus of marine spiders, said to live on coral reefs 

 below high-water mark, and to remain in holes in the rock during 

 high tide, enclosed in cocoons impermeable to the sea-water. At 

 low tide it is stated that they come forth and prey upon small 

 crustaceans. Argyroneta has only one species, A. aquatica, spread 

 throughout Europe and North and Central Asia. It is the well- 

 known " Water-spider," which is so often an object of interest in 

 aquaria. 



