268 AMERICAN SPIDERS 



Calamistrum. The more or less extensive row of curved hairs on 

 the hind metatarsi, used to comb the silk from the cribellum. 



Carapace. The hard dorsal covering of the cephalothorax in the 

 Arachnida. 



Cephalothorax. The united head and thorax of Arachnida and 

 Crustacea. 



Chelicerac. The pincerlike first pair of appendages of the arachnids; 

 in spiders two-segmented, the distal portion or fang used to 

 inject venom from enclosed glands into the prey. 



Chorion. The outer covering or shell of the spider or insect egg. 



Coxa. The basal segment of the leg by means of which it is articu- 

 lated to the body. 



Claw tufts. The pair of tufts of adhesive hairs present below the 

 paired claws at the tip of the tarsi of many spiders. 



Colulus. The slender or pointed appendage immediately in front of 

 the spinnerets of some spiders; in other greatly reduced or seem- 

 ingly missing; the homologue of the anterior median spinnerets 

 or cribellum. 



Coxal glands. The excretory organs of arachnids, in spiders located 

 opposite the coxae of the first and third legs, that collect wastes 

 into a saccule and discharge them through tubes opening behind 

 the coxae; homologous with the nephndia of Peripatus, etc. 



Cribellum. A sievelike, transverse plate, usually divided by a deli- 

 cate keel into two equal parts, located in front of the spinnerets 

 of many spiders; the modified anterior median spinnerets. 



Cuticle. The hard outer covering of an arthropod. 



Deutovum. The resting, spiderlike stage following the shedding of 

 the chorion of the egg; the second egg. 



Dorsum. In general, the upper surface. 



Ecdysis. The process of casting the skin; molting. 



Endite. The plate borne by the coxa of the pedipalps of most spiders, 

 used to crush the prey; the maxilla. 



Epigynum. The more or less complicated apparatus for storing the 

 spermatozoa, immediately in front of the opening of the internal 

 reproductive organs of female spiders. 



Femur. The thigh; usually the stoutest segment of the spider's leg, 

 articulated to the body through the trochanter and coxa and bear- 

 ing the patella and remaining leg segments at its distal end. 



Genitalia. All the genital structures. 



Hackled band. The composite threads of the cribellate spiders, spun 

 by cribellum and combed by the calamistrum. 



