AEANEAE 



417 



Key to the families of Dipneumones here described: 

 a v With cribellum and calamistrurn (Fig. 655). 



&! Eyes all dark-colored (diurnal) ; web usually regular 1. ULOBORIDAE 



& 2 Anterior median eyes dark, the other light-colored (nocturnal) ; web 

 irregular. 



c t Lateral eyes near together 2. DICTYNIDAE 



c 2 All the eyes close together on an eminence 3. FILISTATIDAE 



o 2 Without cribellum and calamistrum. 

 &! Two terminal claws on the feet. 



Cj Six eyes ; 4 spiracles ; ground spiders 4. DYSDEBIDAK 



C 2 Eight eyes present. 

 di Eyes usually in 2 rows. 

 1 First 2 pairs of legs not noticeably longer than the others. 



/ x Fore spinnerets widely separated ; ground spiders 5. DRASSIDAE 



/ 2 Fore spinnerets contiguous ; ground spiders 11. CLUBIONIDAE 



e 2 First 2 pairs of legs much longer than the others ; crab spiders. 



10. THOMISIDAE 



d a Eyes in 3 rows, the middle row being much smaller than the others. 

 6 2 Three terminal claws on the last 3 pairs of feet. 15 - ATTIDAE 



Cj Legs very long, being over 4 times the length of the body 6. PHOLCIDAE 



c 2 Legs not so long. 

 d l Eyes in 2 rows. 



61 Hinder part of spinnerets not very long. 



/! A comb of serrate bristles on the hind foot ; abdomen often globose. 

 /, No such comb. 7 - THERIDIIDAE 



&! Basal segment of mandible with row of teeth on its outer surface ; 



small spiders with irregular webs 8. LINYPHIIDAE 



ff 2 No such mandibular teeth; usually large spiders with regular 



radial webs 9. EPEIRIDAE 



g 3 A semicircular notch at base of leg on penultimate segment. 



13. PlSAURIDAE 



e 2 Hinder pair of spinnerets 

 very long and 2 jointed. 



12. AGELENIDAE 

 d z Eyes in 3 rows . . . 14. LYCOSIDAE 



FAMILY 1. ULOBORIDAE. 



A cribellum and usually a cala- 

 mistrum (Fig. 655) present; lateral 

 eyes farther apart than the 2 pairs 

 of median eyes; web usually round 

 and regular, with radiating spokes 

 joined by cross threads and com- 

 posed in part of loose bands of silk : 

 3 genera, and 6 American species. 



1. ULOBORTTS Latreille. Cephalothorax ovate, rounded behind; eyes 

 all of about the same size: 4 American species. 



U. plumipes Lucas. Length of female 7 mm. ; cephalothorax low ; first 

 pair of legs in the female twice as long as the second, with a bunch of long 

 hairs at the end of the middle segment ; color brown, with a median stripe 



Fig. 655 A, part of fourth leg of 

 Amavrobius; B, ventral view of hinder 

 end of same. 1, calamistrum ; 2, cribel- 

 lum : 3, anterior spinnerets ; 4, middle 

 spinnerets ; 5, posterior spinnerets ; 6, 

 anus. (Cambridge Natural History.) 



